Category Archives: Conservation Biology

A Dilemma of Ecological Science

To save myself from the current problems of funding science in general in North America, I would like to ask an impossible but perhaps interesting question: What research would ecologists carry out if they had ten billion dollars of funding? This of course is a ridiculous question, but it is interesting because it would focus our minds on what the major issues of our time are in the ecological sciences and where to go next. The history of the hard sciences like physics, chemistry and medicine is punctuated with a specification of the most important issues that need solving. These specifications change as progress occurs in each science so that there are many books about successes in solving problems in these hard sciences. Could we do this in ecology and what might this list of problems and possible solutions look like?

The first response is that ecology is not a hard science like physics and chemistry with a plethora of well-defined laws. I think this is a cop-out. Ptolemy and Newton and Darwin did not avoid these questions and forged new ways of thinking in their respective sciences. A second response is that ecological science deals with contingent events much as geological science does. We can understand volcano eruptions and tsunamis, but we cannot predict if, when and where they will occur in the same way we can predict that a bridge will fall over if the construction materials are not correct.

We have in ecology today two major schools of thought about what are the most critical issues that ecologists need to investigate. The first school of thought is that we need to understand how populations and communities are structured, how their components interact, and how much these ecosystems vary in different parts of the Earth. We have adequate to good methods to investigate these questions but lack the funding at present. The major unanswered questions within this paradigm are how these ecosystems will respond to global change with respect to human population growth and climate change. But these questions can only be answered with long-term studies, both observational and experimental. The system is hampered by two constraints – the length of an individual scientist’s research, and the short-term view of funding which assumes all these questions can be answered with 3-5-years of research funding. We can achieve success only by establishing teams of ecologists that focus on major questions and cooperate with observations and experiments that exceed the ability of a single scientist with a limited research lifespan. Success on this front can be seen most readily in the aquatic sciences, avian and mammal ecology and least readily in the ecology of the small guys – insects, bacteria, viruses. So, our current understanding in population and community ecology is best with the species we can eat and with large species rather than small. There is no question but that these advances in ecological knowledge are more difficult in the tropical countries with more complex ecosystems and in general less money for research.

The second major school of thought in the ecological sciences is biodiversity science. This school of thought passes over all the problems of ecosystem ecology to describe the species that exist on Earth. This is a gigantic problem because of the large number of undescribed species. We make progress on this list slowly, and at present if you pick up a plant, small animal, and insect, or a bacterium among other species it is impossible to assign a taxonomic name and description. Progress in identification is progress is moving rapidly because of DNA technology but the desirable target of having an inventory of life on Earth is still a long way off.

Given that we have this partial inventory, the major issue of biodiversity science is the problem of extinction – we do not want to see any species go extinct. This is a tall order but an important one. And it is here that the two major schools of ecology must join forces because you cannot understand extinction unless you have adequate knowledge of the role of each species in the ecosystem. If you read the news today, you will become rather depressed because of reported rates of extinction at the present time. The sentiment is good; the data are poor. An unresolved problem is that most species are rare. We humans notice the big species and the colourful birds and insects, but rare species are difficult to study. News media report every species that was thought to be extinct because none were seen for perhaps 20 or 30 years but now a few were found again. With enough funding and person-power ecologists could analyse the details of extinction in a few species but there is no hope that this could be done for the small fauna that are rare and expensive to find.

So, the take home message is that the two major schools of ecology must interact more to achieve success on both fronts but the shortage of funding and the shortage of ecologists in each of the two major areas are limiting. At some point this will change. There are many very wealthy people in western countries who could fund a very large sum of money for ecological science. To date such a financial event is rare, and a possible reason for this is that the ecological sciences do not support economic growth and human health in the same way that physics, chemistry and medicine do. The ecological costs of economic growth are largely ignored, and the two largest of our global problems are climate change and human population growth which exceeds the carrying-capacity of the Earth.  Both issues operate on a time scale greater than the average human lifespan, so we pass the problem on to our children. Ecological science is caught in the trap of not increasing the god of GDP and reporting more problems every day than it is solving. We have a long way to go, and it is important that ecologists look at the long-term and adjust their scientific goals accordingly. Much talk is good if it leads to much action. But action cannot be done without funding.

Duda, M.D., Beppler, T., Austen, D.J., and Organ, J.F. 2022. The precarious position of wildlife conservation funding in the United States. Human Dimensions of Wildlife 27(2): 164–172. doi:10.1080/10871209.2021.1904307.

Gallo-Cajiao, E., Archibald, C., Friedman, R., et al. 2018. Crowdfunding biodiversity conservation. Conservation Biology 32(6): 1426–1435. doi:10.1111/cobi.13144.

Guénard, B., Hughes, A.C., and Williams, G.A. 2025. Limited and biased global conservation funding means most threatened species remain unsupported. Proceedings of the National Academy of Sciences 122(9): 2412479122. doi:10.1073/pnas.2412479122.

Lant, M., Bendel, C.R., Parent, C.J., and Kaemingk, M.A. 2025. A need for assessing the resiliency of conservation funding. Ecology and Society 30(3): 9. doi:10.5751/es-16322-300309.

Papp, C.R., Scheele, B., Rákosy, L., and Hartel, T. 2022. Transdisciplinary deficit in large carnivore conservation funding in Europe. Nature Conservation 49: 31–52. doi:10.3897/natureconservation.49.81469.

Problems in Funding Biological Conservation Research

Everyone is in favour of preventing extinctions and the job of the conservation ecologist is to specify how to achieve this scientific goal. That scientific job leads into a maelstrom of problems that have been discussed extensively in the literature. I want to concentrate today on the related question of how much funding is needed and available for conservation and how it can be used most efficiently. The literature on these aspects of conservation action is extensive and I discuss here only a small part of the problems and approaches.

Funding for scientific research has always been limited and in a democratic society would improve only if public interest in research becomes stronger. This is now happening, but the governments of western countries are pulled in many directions for funding and the ecological data needed for protecting threatened and endangered species and ecosystems cannot be obtained by voluntary citizen science, valuable though it is. One of the funding success stories from the United States has been the enactment of the Pittman-Robertson Act of 1937 (Duda et al. 2022). Wildlife conservation in the USA has been supported by a tax on the purchases of guns and ammunition by hunters and those funds were given to each state to support wildlife conservation. But the number of hunters has declined in the USA although the sales of lethal weapons continue to increase. Sport shooters who are not hunters now provide about half of these tax dollars for conservation, and there has been a move to broaden the tax base to more outdoor activities.

Philanthropic funding has contributed greatly to increased funding for conservation work, but these funds are often country-specific (Yang et al. 2024), and while they benefit wealthy countries, they are sparse in the poorer countries with high species richness and where conservation is even more essential. Yang et al. (2024) discuss the rising philanthropic funding for biodiversity conservation in China while recognizing that while conservation funding is rising it represents <1% of all the philanthropic funding in China. While there is a massive amount of philanthropy that contributes to medical science, there is a strong need for philanthropic funding to increase in all the wealthy countries. Kedward et al. (2023) discuss why private funding alone will not be able to deliver positive achievements for conservation goals. They point out that conservation funding is approximately 5-7 times lower than is needed to reverse biodiversity losses, which argues for direct public funding of conservation by governments. Private investors wish to have some financial return for their investments which can lead to perverse incentives and “greenwashing” with no positive results for biodiversity conservation.

A further concern is that conservation research requires a long-term investment combined with a high tolerance for uncertainty. Given that we can achieve both private and governmental funding for conservation, we find two critical decisions – what species do we focus on since we cannot do all species, and what scale must be achieved to stop biodiversity loss. It is no surprise to conservation ecologists that both taxonomic and aesthetic biases extend throughout biodiversity research. Adamo et al. (2020) compiled for the European Union the funding for plants and animals with the EU over the last 3 decades. They found that animal species obtained three times more funding than plant species. This large-scale approach turned up an array of surprises. In plants for example, species found at northern latitudes with broad distributions and with blue flowers obtained more funding regardless of whether or not they were in danger of extinction.

The species ecologists are attracted to are obvious to any naturalist. We are concerned more about elephants than small rodents. We worry more about sequoias than we do about algae. 

The scale question in biodiversity research is the second major issue. Protected areas like National Parks are a key component of safeguarding biodiversity, and setting aside these protected areas is a major effort in conservation. But when one looks at the global scale and compile only those protected areas that are properly resourced with adequate staff and a sufficient budget, Coad et al. (2019) found that only 4-9% of terrestrial amphibians, birds, and mammals are adequately represented in protected areas. Hebblewhite et al. (2022) evaluated the Yellowstone to Yukon (Y2Y) large-landscape conservation achievements since its establishment in 1993. The focal species of this large region was the grizzly bear, an umbrella species for this large area of 1.3 million sq. km in western North America. During the last 25 years the amount of protected area in this particular landscape grew by 8%, achieving a total of 18% of the landscape in national parks and reserves, a major conservation success. This program is a clear success but not yet achieving the 30% proposed by the Global Biodiversity Framework of 2022 (Saunders et al. 2023).

The scale issue is critical at small scales as well, and the critical point is that detailed small scale research efforts are essential for conserving the biodiversity in all protected areas. Most conservation research is at small scale with a limited budget and working on a limited area with a time frame of 3 years. Yet the purpose of many research grants is to achieve results that will flow through into policy at the government level. LeFlore et al. (2022) evaluated how many small-scale studies in the flora and fauna of coastal marine environments were utilized in policy actions. They found that only 40% of these marine studies were reported to result in a positive outcome for conservation. Specific reliable scientific data are a prerequisite to defining action plans for conservation but there needs to be more interaction between government policy makers and scientists collecting relevant data. Reliable data are necessary for proper conservation policy actions but not sufficient.

Adamo, M., Sousa, R., Wipf, S., Correia, R.A., Lumia, A., Mucciarelli, M. & Mammola, S. (2022) Dimension and impact of biases in funding for species and habitat conservation. Biological Conservation, 272, e109636.doi: 10.1016/j.biocon.2022.109636.

Coad, L., Watson, J.E.M., Geldman, J., Burgess, N.D., Leverington, F., Hockings, M., Knights, K. & Di Marco, M. (2019) Widespread shortfalls in protected area resourcing undermine efforts to conserve biodiversity. Frontiers in Ecology and the Environment, 17, 259-264.doi: 10.1002/fee.2042.

Duda, M.D., Beppler, T., Austen, D.J. & Organ, J.F. (2022) The precarious position of wildlife conservation funding in the United States. Human Dimensions of Wildlife, 27, 164-172.doi: 10.1080/10871209.2021.1904307.

Hebblewhite, M., Hilty, J.A., Williams, S., Locke, H., Chester, C., Johns, D., Kehm, G. & Francis, W.L. (2022) Can a large-landscape conservation vision contribute to achieving biodiversity targets? Conservation Science and Practice, 4, e588.doi: 10.1111/csp2.588.

Kedward, K., Ermgassen, S.z., Ryan-Collins, J. & Wunder, S. (2023) Heavy reliance on private finance alone will not deliver conservation goals. Nature Ecology & Evolution, 7, 1339-1342.doi: 10.1038/s41559-023-02098-6.

LeFlore, M., Bunn, D., Sebastian, P. & Gaydos, J.K. (2022) Improving the probability that small‐scale science will benefit conservation. Conservation Science and Practice, 4, e571.doi: 10.1111/csp2.571.

Saunders, S.P., Saunders, S.P., Grand, J., & Price, J. (2023). Integrating climate‐change refugia into 30 by 30 conservation planning in North America. Frontiers in Ecology and the Environment 21(2): 77-84. doi:10.1002/fee.2592.

Yang, F., Tao, Z. & Zhang, L. (2024) Trends and dynamics of philanthropic funding for biodiversity conservation in China. Conservation Science and Practice, 6, e13059.doi: 10.1111/csp2.13059.

On the Forest Industry and why we might worry about our forests

This blog differs from my usual in being a plea to read one book on the forest industry in Australia and why we might worry in every country about our forestry practices. The book is by David Lindenmayer and in it is a capsular summary of the evidence presented about the state of the forest industry in Australia and the myths that are continually presented about sustainability of forests wherever they are. If you teach students or adults about environmental problems, you could discuss whether these myths apply to your part of the world. For more details on the evidence behind these statements read the book. Much action is needed to eliminate these myths.

Lindenmayer, David. (2024) “The Forest Wars” Allen and Unwin, Sydney, Australia. ISBN: 978 76147 075 2.  Available as a paperback or a kindle book from Allen and Unwin.
Allen and Unwin: The Forest Wars

I copy here the opening 2 pages of this book:

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The Myths

  1. The forest will grow back.
  2. Animals just move on.
  3. Only a small proportion of the forestry estate is logged.
  4. Only small patches of the forest are logged each year, so the forest remains intact.
  5. Forestry departments do proper pre-logging surveys for animals.
  6. Detecting more animals means a species is OK.
  7. Retaining a few big trees on logged sites will save the animals.
  8. We can solve the animal housing crisis with nest boxes.
  9. Selective logging is better than clearfelling.
  10. It is good to ‘clean up’ storm and fire-damaged forest.
  11. Forest gardening heals country.
  12. We need to log forests to keep them safe.
  13. Forests will be less flammable if we thin them.
  14. Logging has the same effects as wildfires.
  15. We can burn our way out of the wildfire problem.
  16. Tall, wet forests [in Australia] were open and park-like at the time of the British invasion.
  17. Cultural burning was practiced all over Australia.
  18. Most wood cut in a logging coupe gets milled for sawn lumber.
  19. We need native forest logging to build and furnish our houses.
  20. Without native forest logging we will bring in imports that kill Orangutans.
  21. Native forest logging is value added.
  22. Logging is good business.
  23. Logging is more lucrative than other forest uses.
  24. Native forest logging employs tens of thousands of people.
  25. Australia has the best regulated native forest logging industry in the world.
  26. Government regulators will keep the bastards honest.
  27. Regulations protect old-growth forest.
  28. Regional forest agreements solved the forest wars.
  29. Melbourne is not Moscow – the spy who came in from the forest.
  30. Native forest logging is sustainable.
  31. Forest industries are enduring industries.
  32. There is nothing to worry about – carbon dioxide is natural.
  33. The best way to tackle climate change is to cut down forests and regrow them.
  34. Burning biomass from forests is better than burning fossil fuels.
  35. We already have enough reserves.
  36. Intact forests are selected for reserves.
  37. Politicians keep their promises about preserving forests.

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With thanks to David Lindemayer and his research group in Canberra.

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Whither Demography in an Era of Biodiversity Science?

Biodiversity science has overtaken traditional ecological science in an important way that bears some discussion. Biodiversity science seeks as its main goal to protect species from declining to extinction. It overlaps traditional population and community ecology partly by concentrating on iconic species that are declining in abundance and thus trying to prevent species loss, but the major focus of biodiversity science is on the species composition of communities and ecosystems and trying to understand what factors are driving deleterious changes. This task is difficult to complete currently because of a shortage of research time, person-power and money, so we are driven to select relatively few ecosystems to concentrate our conservation efforts upon. If we cannot do everything for all species, we must choose what to do at the present time, and this releases a cascade of discussions and arguments about what species are ‘flagship’, “umbrella”, or “keystone” in any particular community or ecosystem (Barua 2011).

Now we can go in two directions. We can take the simplest route and say that all species are of equal importance, so the objective of biodiversity science becomes ‘occupancy” – is species X still existing in ecosystem Y? Occupancy can be established in a variety of ways from simple visual sightings, traps, cameras, e-DNA, to electronic sound recording devices. Occupancy for species in a particular ecosystem is a useful parameter for biodiversity studies but it is alpha-level ecology for understanding community or ecosystem dynamics. Determining occupancy every month, year, or decade will provide a start in community and ecosystem understanding but in order to achieve its goal as a science it needs population and community ecology to measure and understand the dynamics underlying occupancy, and this is the more complicated route that we can take. The defining science for this second level of understanding comes from dynamics, both population and community dynamics.

Population dynamics is necessary for determining if a particular species is declining in numbers or biomass, and what the causes are of the observed trends. We are led into demography, the measurement of births, deaths, and movements in animals and the equivalent parameters in plants. But now we run into the most serious problem of determining what parameters are the causal agents of declines in abundance and what procedures will alleviate species declines. If we have many species in our community or ecosystem, the requirements for research are extravagant, given the current workers and dollars currently available for environmental science. All ecologists want to protect biodiversity but how might we best achieve that goal?

We fall back at this point into simple general procedures for biodiversity conservation like designation of national parks or protected areas with the hope that the biodiversity of the designated area will not decline. We do not have the person-power to have frequent occupancy surveys for any national park, much less to have the investigations of why an iconic species is declining in an area. At present we must fall back on ‘umbrella species’ or ‘flagship species’ (Simberloff 1998). There is an extensive literature on this approach to biodiversity conservation and recent reviews, some critical (Tälle et al. 2023), others somewhat more positive (Sumbh and Hof 2022, Clark-Wolf et al. 2024), combining this approach with food web structure (Wang and Zhou 2023).   

Complicating the whole issue of protecting biodiversity is the issue of cryptic species, undescribed species, and rare species that are capable of taxonomic and ecological resolution but only at a large cost and a long timeframe to achieve results (Cheng et al. 2024). Once we are successful in protecting our communities and ecosystems, we immediately face the demographic issue of what affects the abundance of all the species of interest, and then the social and political issue of the funds available for conservation of these species. We need to bring the approaches of biodiversity science and classical demographic ecology together to achieve conservation goals. We can do this only by recognizing that knowing occupancy is not enough to achieve conservation success, and we need to follow up with population and community ecology within the context of food webs so that we can understand trends in abundance and finally propose possible actions for conservation management. We have much to do.

Barua, M. (2011) Mobilizing metaphors: the popular use of keystone, flagship and umbrella species concepts. Biodiversity and Conservation, 20, 1427-1440.doi:10.1007/s10531-011-0035-y.

Cheng, R., Luo, A., Orr, M., Ge, D., Houu, Z.e., Qu, Y., Guo, B., Zhang, F., Sha, Z., Zhao, Z., Wang, M., Shi, X., Han, H., Zhou, Q., Li, Y., Liu, X., Shao, C., Zhang, A., Zhou, X. & Zhu, C. (2024) Cryptic diversity begets challenges and opportunities in biodiversity research. Integrative Zoology, (in press). doi: 10.1111/1749-4877.12809.

Clark-Wolf, T.J., Holt, K.A., Johansson, E., Nisi, A.C., Rafiq, K., West, L., Boersma, P.D., Hazen, E.L., Moore, S.E. & Abrahms, B. (2024) The capacity of sentinel species to detect changes in environmental conditions and ecosystem structure. Journal of Applied Ecology, (in press). doi: 10.1111/1365-2664.14669.

Simberloff, D. (1998) Flagships, umbrellas, and keystones: is single-species management passe in the landscape era? Biological Conservation, 83, 247-257.doi: 10.1016/S0006-3207(97)00081-5.

Sumbh, O. & Hof, A.R. (2022) Can pikas hold the umbrella? Understanding the current and future umbrella potential of keystone species Pika (Ochotona spp.). Global Ecology and Conservation, 38, e02247.doi: 10.1016/j.gecco.2022.e02247.

Tälle, M., Ranius, T. & Öckinger, E. (2023) The usefulness of surrogates in biodiversity conservation: A synthesis. Biological Conservation, 288; e110384. doi: 10.1016/j.biocon.2023.110384.

Wang, Q., Li, X.C. & Zhou, X.H. (2023) New shortcut for conservation: The combination management strategy of “keystone species” plus “umbrella species” based on food web structure. Biological Conservation, 286, 110265.doi: 10.1016/j.biocon.2023.110265.

How Much Can Ecologists Lie?

An ethical dilemma arises in ecology for scientists who have strong beliefs about climate change and the protection of biodiversity. Should you tell lies in your scientific papers or to the media regarding ecological issues? In essence the simple answer is never. Science is the search for the truth and the truth should be obtained from empirical evidence. This does not mean that a scientist cannot have any opinions about which you can shout very loudly, if for example you think that poached eggs are better than scrambled eggs. But there should be a general taboo about lying and we should keep a sharp distinction that opinions ≠ evidence.

But in the real world these distinctions are not always clear. How much should you as a scientist bend or gloss over the evidence? If you find that a particular pollutant will have a 75% chance of killing fish in a river system, should you stand aside as an industry argues that there is a 25% chance that nothing will happen, and profits must come before caution. In these kinds of discussions environmentalists always lose because of the precautionary principle and information is never 100% precise. The temptation is to avoid losing by lying, stretching the evidence, or shouting.

In this era of the climate disaster, it is difficult to restrain from talking about what will happen in the future. While opinions fly back and forth on what is happening, whether it will all reverse, and how soon changes will occur, ecologists must remain trustworthy by countering misinterpretations of ecological trends without rancour. When our research is incomplete, we should say so and indicate what needs to be done next to fill in the gaps in knowledge. If we are wrong in our predictions, we should admit it and discuss why. We need to point out the problems and the potential consequences from what we know today. This is not as difficult as it sounds, and it requires only to draw a line between the existing evidence and likely extrapolations from current knowledge.

A major part of current misinformation on social media about scientific issues is that existing evidence is blown out of proportion in an attempt to get some kind of specific action by governments or corporations. Lies or disinformation are more interesting to the media than the details of what is actually reliable knowledge. Uncertain predictions about future changes by scientists are often translated in social media as certain predictions. Perhaps the most important but most difficult aspect of predictions is the need to go back one or more years and list the predictions that were made and evaluate how accurate they were. Model systems for the sciences are perhaps earthquake predictions and weather predictions. While we know a great deal about the geological causes of earthquakes and have mapped major faults along which they occur, so all would agree that we “understand earthquakes scientifically”, we are not able to predict exactly where and when the next major quake will occur. Similarly we are all familiar with weather predictions which are limited to short time intervals even though we have detailed knowledge of the physical laws that govern air mass movements.

Some samples of the very large literature on forecasting earthquakes (Fallou et al. 2022, Wikelski et al. 2020), and on biotic extinctions (Cowie et al. 2022, Kehoe et al. 2021, Lambdon and Cronk 2020, Nikolaou and Katsanevakis 2023, Williams et al. 2021) provide an introduction to finding out how scientists deal with the uncertainties of prediction in these two example areas of science. Knowledge is power but it is not infinite power, and all scientists should qualify their predictions or projections as possibly in error. Lying about complex questions is not part of science.  

Cowie, R.H., Bouchet, P. & Fontaine, B. (2022) The Sixth Mass Extinction: fact, fiction or speculation? Biological Reviews, 97, 640-663.doi: 10.1111/brv.128161.

Fallou, L., Corradini, M. & Cheny, J.M. (2022) Preventing and debunking earthquake misinformation: Insights into EMSC’s practices. Frontiers in Communication, 7, 993510.doi. 10.3389/fcomm.2022.993510

Kehoe, R., Frago, E. & Sanders, D. (2021) Cascading extinctions as a hidden driver of insect decline. Ecological Entomology, 46, 743-756.doi: 10.1111/een.129851.

Lambdon, P. & Cronk, Q. (2020) Extinction dynamics under extreme conservation threat: The Flora of St Helena. Frontiers in Ecology and Evolution, 8, 41.doi: 10.3389/fevo.2020.00041.

Nikolaou, A. & Katsanevakis, S. (2023) Marine extinctions and their drivers. Regional Environmental Change, 23, 88.doi: 10.1007/s10113-023-02081-8.

Wikelski, M., Mueller, U., Scocco, P., Catorci, A., Desinov, L.V., Belyaev, M.Y., Keim, D., Pohlmeier, W., Fechteler, G. & Martin Mai, P. (2020) Potential short-term earthquake forecasting by farm animal monitoring. Ethology, 126, 931-941.doi: 10.1111/eth.13078.

Williams, N.F., McRae, L. & Clements, C.F. (2021) Scaling the extinction vortex: Body size as a predictor of population dynamics close to extinction events. Ecology and Evolution, 11, 7069-7079.doi: 10.1002/ece3.7555.

On Discourse and Evidence

A major problem that bedevils society as well as science today is the distinction between opinion and evidence. The world is awash in opinions and short of evidence for many questions that fill the news media as well as the scientific literature. In trying to evaluate this statement we should recognize that there are many important issues for which we have no evidence but only beliefs. A current discussion in the news media is whether or not any particular country should spend 2% of its GDP on military expenses. Much hot air follows from these discussions because as an individual person you have no evidence one way or the other for different points of view, spend more, spend less. You will have an opinion that everyone should respect but for this and many issues any evidence that can be cited is vague. Discussion on many issues like this example are important and should be civilized but often are not.

But there are a range of issues for which scientific evidence is available. The first rule of discourse on these issues ought to be that you as a person are allowed to have any opinion you wish but you must be able to present evidence to support your opinions. You should be allowed as a person to proclaim that the Earth is not round but flat and provide the evidence one way or the other. More serious issues with different opinions involve issues like vaccination for a particular disease. On these issues scientists can only advise and provide evidence. But if a vaccine X for example has a complex side effect rate of 1 person in 1000, you could always argue that you are that one person and you are opposed to vaccination X.

How does all this relate to ecological science? First, we should recognize that many of the arguments in the ecological literature are about opinions rather than evidence. In many cases this should lead to more studies of particular problems to gather more evidence. But as we see with climate change research the evidence is accumulating but varies greatly in quality and time span from area to area and from taxonomic group to taxonomic group. We cannot agree whether our research should be focused on the oceans or on land, or on birds rather than mammals or insects. We cannot do everything, and the consequence is that ecological research funding is driven in many directions depending on who is on the committee dispersing funding and what their opinions are. The result is that for large scale problems like climate change we have convinced most people that it is a reality, but we cannot agree on the details of future change. So, we build models with past data and try to project them into the future with uncertain confidence.

The consequence is that the ecological world is awash in opinions in the same way as other parts of society, and in support of opinions the evidence often gets lost. The main problem here is that opinions are generated rapidly while evidence accumulates slowly. We see this more readily in medical science in which the media trumpets treatment X rather than Y with opinions and little evidence. We cannot demand answers to important questions tomorrow when the problem spans years or decades for evidence to accumulate. 

Ecology like every science becomes more complicated with age, and a fisheries biologist trained 40 years ago lives in a different world from one trained today. The accumulated evidence from research changes our list of important questions illustrated well by the reviews of progress in conservation science by Sutherland et al. (2022, 2023) and Christie et al. (2023), in predator- prey dynamics by Sheriff et al. (2020), wildlife management by Hone et al. (2023), and in insect conservation by Saunders et al. (2020). Understanding and solving ecology problems must rely more on evidence and less on opinions.

Christie, A.P., Christie, A.P., Morgan, W.H. & Sutherland, W.J. (2023) Assessing diverse evidence to improve conservation decision‐making. Conservation Science and Practice, 5, e13024.doi. 10.1111/csp2.13024

Hone, J., Drake, A. & Krebs, C.J. (2023) Evaluation Options for Wildlife Management and Strengthening of Causal Inference. BioScience, 73, 48-58.doi: 10.1093/biosci/biac105.

Saunders, M.E., Janes, J.K. & O’Hanlon, J.C. (2020) Moving On from the Insect Apocalypse Narrative: Engaging with Evidence-Based Insect Conservation. BioScience, 70, 80-89.doi: 10.1093/biosci/biz143.

Sheriff, M.J., Peacor, S.D., Hawlena, D. & Thaker, M. (2020) Non-consumptive predator effects on prey population size: A dearth of evidence. Journal of Animal Ecology, 89, 1302-1316.doi: 10.1111/1365-2656.13213.

Sutherland, W.J. & Jake M. Robinson, D.C.A., Tim Alamenciak, Matthew Armes, Nina Baranduin, Andrew J. Bladon, Martin F. Breed, Nicki Dyas, Chris S. Elphick, Richard A. Griffiths, Jonny Hughes, Beccy Middleton, Nick A. Littlewood, Roger Mitchell, William H. Morgan, Roy Mosley, Silviu O. Petrovan, Kit Prendergast, Euan G. Ritchie,Hugh Raven, Rebecca K. Smith, Sarah H. Watts, Ann Thornton (2022) Creating testable questions in practical conservation: a process and 100 questions. Conservation Evidence Journal, 19, 1-7.doi. 10.52201/CEJ19XIFF2753

Sutherland, W.J., Sutherland, W.J., Bennett, C. & Thornton, A. (2023) A global biological conservation horizon scan of issues for 2023. Trends in Ecology & Evolution, 38, 96-107.doi. 10.1016/j.tree.2022.10.005

Should Ecology Abandon Popper?

The first question I must ask is whether you the reader have ever heard of Karl Popper. If the answer is no, then you could profit from reading Popper (1963) before you read this. An abbreviated version of the Popperian approach to science is presented in a short paper by Platt (1963) The simplest version of Popper and Platt is that we should have a hypothesis with specific predictions and one or more alternative hypotheses with other predictions, and science advances by finding out which hypotheses could be rejected with empirical evidence. The focus of this blog is on a recent paper by Raerinne (2024) claiming that Popperian ecology is a delusion. This is a claim well worth discussing particularly since most of the sciences progress using a Popperian approach to testing hypotheses.

To begin perhaps we should recognize two kinds of papers that appear in ecological journals. A very large set of ecological papers appear to be largely or entirely descriptive natural history typically of past or present events with no hypotheses in mind. Many of these papers end with a conclusion that could be designated as a hypothesis but with little discussion of alternatives. These papers can be very valuable in giving us the state of populations, communities, or ecosystems with recommendations for changes that should be made to alleviate developing problems. A good example are papers describing forest and grassland fires of recent years which can end with some management recommendations, and perhaps with alternative recommendations. These recommendations usually arise from experience and judgements, and they may or not be valid. The Popperian approach would be to set up hypotheses and test them empirically, but if we are people of action, we press onward with a preferred management action. The non-Popperian approach would be very efficient if we were correct in our diagnosis, and in many cases this approach works well. The basis of the issue here is what is evidence in ecology and how should it be sharpened into recommendations for conservation and management.  

The Popperian approach to ecological science is to recognize problems that require a solution to increase our knowledge base, and to suggest a series of alternative set of mechanisms that could solve or alleviate the problem. Ecological papers supporting this approach can often be recognized by searching for the word “hypothesis” in the text. A simple example of this Popperian approach could be finding the causes of the continuing decline of a commercial fishery. The decline might be due to predation on the target fish or invertebrate, a disease, added pollution to the water body, climate change increasing the water temperature and thus metabolic functions, introduced species of competitors for food or space. One or more of these causal factors could be involved and the job of the ecologist is to find out which one or several are diagnostic. Given the complexity of ecological problems, it is typically not possible to test these alternative hypotheses in one grand experiment, and the typical approach will involve adaptive management or evidence-based conservation (Gillson et al. 2019, Serrouya et al., Westgate et al. 2013). Complexity however should not be used as an excuse to do poor science.

What is the alternative if we abandon Popper? We could adopt the inductive approach and gather data that we put together with our judgement to declare that we have a correct answer to our questions, “seat of the pants” ecology. But this approach is heavily dependent on the idea that “the future will be like the past”. This approach to ecological problems will be most useful for the very short term. The simplest example comes from weather forecasting in which the prognosis for today’s weather is what it was like yesterday with minor adjustments. We could observe trends with this approach but then we must have a statistical model that predicts, for example, that the trend is linear or exponential. But the history of science is that we can do much better by understanding the mechanisms underlying the changes we see. A good overview of the dilemmas of this inductive approach for conservation biology is provided by Caughley (1994). The operative question here is whether the inductive approach achieves problem resolutions more efficiently than the Popperian approach through conjecture and refutation.

Raerinne (2023, 2024) does biology in general and ecology in particular a disservice in criticizing Popper’s approach to ecology by arguing that ecology should not be criticized nor evaluated from the Popperian perspective. I think this judgement is wrong, and Raerinne’s conclusion arises from a philosophical viewpoint which could well have little applicability to how ecologists solve empirical problems in the real world. But you can judge.  

Carducci, A., Federigi, I. & Verani, M. (2020) Airborne transmission and its prevention: Waiting for evidence or applying the Precautionary Principle? Atmosphere, 11 (7), 710.doi: 10.3390/atmos11070710.

Caughley, G. (1994) Directions in conservation biology. Journal of Animal Ecology, 63, 215-244. doi: 10.2307/5542.

Gillson, L., Biggs, H. & Rogers, K. (2019) Finding common ground between adaptive management and evidence-based approaches to biodiversity conservation. Trends in Ecology & Evolution, 34, 31-44.doi: 10.1016/j.tree.2018.10.003.

Platt, J.R. (1964) Strong inference. Science, 146, 347-353.doi: 10.1126/science.146.3642.347.

Popper, K.R. (1963) Conjectures and Refutations: The Growth of Scientific Knowledge. Routledge and Kegan Paul, London.

Raerinne, J. (2023) Myths of past biases and progress in biology. Theory in Biosciences, 142, 383-399.doi: 10.1007/s12064-023-00403-2.

Raerinne, J. (2024) Popperian ecology is a delusion. Ecology and Evolution, 14, e11106.doi: 10.1002/ece3.11106.

Serrouya, R., Seip, D.R., Hervieux, D., McLellan, B.N., McNay, R.S., Steenweg, R., Heard, D.C., Hebblewhite, M., Gillingham, M. & Boutin, S. (2019) Saving endangered species using adaptive management. Proceedings of the National Academy of Sciences, 116, 6181-6186.doi: 10.1073/pnas.1816923116 .

Westgate, M.J., Likens, G.E. & Lindenmayer, D.B. (2013) Adaptive management of biological systems: A review. Biological Conservation, 158, 128-139.doi: 10.1016/j.biocon.2012.08.016 .

Biodiversity Science

Protecting biodiversity is a goal of most people who value the environment. My question is what are the goals of biodiversity science and how do we achieve them? Some history is in order here. The term ‘biodiversity’ was coined in the 1980s as the complete biosphere including all species and ecosystems on Earth. The idea of cataloguing all the species on Earth was present many decades before this time, since the origin of the biological sciences. By the 1990s ‘biodiversity conservation’ became a popular subject and has grown greatly since then as a companion to CO2 emissions and the climate change problem. The twin broad goals of biodiversity science and biodiversity conservation are (1) to name and describe all the species on Earth, and (2), to protect all species from extinction, preventing a loss of biodiversity. How can we achieve these two goals?

The first goal of describing species faces challenges from disagreements over what a species is or is not. The old description of a species was to describe what group it was part of, and then how different this particular species was from other members of the group. In the good old days this was primarily based on reproductive incompatibility between species, if no successful reproduction, must be a new species. This simple common-sense view was subject to many attacks since some organisms that we see as different can in fact interbreed. Lions and tigers breed together and are an example, but if their interbred offspring are sterile, clearly, they are two different species. But many arguments arose because there was no data available for 99% of species to know if they could interbreed or not. The fallback position has been to describe the anatomy of a potential species and its relatives and judge from anatomy how different they were. Endless arguments followed, egged on by naturalists who pointed out that if the elephants in India were separated by a continent from elephants in Africa, clearly, they must be different species defined by geography. Many academic wars were fought over these issues.

Then in 1953 the structure of DNA was unravelled, and a new era dawned because with advances in technology of decoding genes we could describe species in a completely new way by determining how much DNA they had in common. But what is the magic percentage of common DNA? Humans and chimpanzees have 98.6% of their DNA in common, but despite this high similarity no one argues that they are the same species.

Despite this uncertainty the answer now seems much simpler: sequence the DNA of everything and you will have the true tree of life for defining separate species. While this was a dream 20 years ago, it is now a technical reality with rapid sequencing methods to help us get criminals and define species. Problem (1) solved?

Enter the lonely ecologist into this fray. Ecologists do not just want names, they wish to understand the function of each of the ‘species’ within communities and ecosystems, how does all this biodiversity interact to produce what we see in the landscape? For the moment we have approximately 10 million species on Earth, but somewhere around 80% of these ‘species’ are still undescribed. So now we have a clash of biodiversity visions, we cannot describe all the species on Earth even on the time scale of centuries, so we cannot achieve goal (1) of biodiversity science in any reasonable time. We have measured the DNA sequence of thousands of organisms that we can capture but we cannot describe them formally as species in the older sense. Perhaps it is akin to having all the phone numbers in the New York City phone book but not knowing to whom the numbers belong.

But the more immediate problem comes with objective (2) to prevent extinctions. Enter the conservation ecologist. The first problem is discussed above, we ecologists have no way of knowing how many species are in danger of extinction. We must look for rare or declining species, but we have complete inventory for few places on Earth. We must concentrate on large mammals and birds, and hope that they act as umbrella species and represent all of biodiversity. When we do have information on threatened species, for the most part there is no money to do the ecological studies needed to reverse declines in abundance. If there is money to list species and give a recovery plan on paper, then we find there is no money to implement the recovery plan. The Species-At-Risk act in Canada was passed in 2002 and has generated many recovery plans mostly for vertebrate species that have come to their attention. Almost none of these recovery plans have been completed, so in general we are all in favour of preventing extinctions but only it if costs us nothing. By and large the politics of preventing extinctions is very strongly supported, but the economic value of extinctions is nearly zero.

None of this is very cheery to conservation biologists. Two approaches have been suggested. The first is Big Science, use satellites and drones to scan the Earth every year to describe changes in landscapes and from these images infer biodiversity ‘health’. Simple and very expensive with AI to the rescue. But while we can see largescale landscape changes, the crux is to do something about them, and it is here that we fail because of the wall of climate change that we have no control over at present. Big Science may well assist us in seeing patterns of change, but it produces no path to understanding food webs or mediating changes in threatened populations. The second is small-scale biodiversity studies that focus on what species are present, how their numbers are changing, and what are the causes of change. Difficult, possible, but very expensive because you must put biologists in the field, on the ground to do the relevant measurements over a long-time frame. The techniques are there to use, thanks to much work on ecological methods in the past. What is missing again is the money. There are a few good examples of this small-scale approach but without good organization and good funding many of these attempts stop after too few years of data.

We are left with a dilemma of a particular science, Biodiversity Science, that has no way of achieving either of its two main objectives to name and to protect species on a global level. On a local level we can adopt partial methods of success by designating and protecting national parks and marine protected areas, and by studying only a few important species, the keystone species of food webs. But then we need extensive research to determine how to protect these areas and species from the inexorable march of climate change, which has singlehandedly complicated achieving biodiversity science’s two goals. Alas at the present time we may have another science to join the description of economics as a “dismal science” And we have not even started to discuss bacteria, viruses, and fungi.

Coffey, B. & Wescott, G. (2010) New directions in biodiversity policy and governance? A critique of Victoria’s Land and Biodiversity White Paper. Australasian Journal of Environmental Management 17: 204-214. doi: 10.1080/14486563.2010.9725268.

Donfrancesco, V., Allen, B.L., Appleby, R., et al. (2023) Understanding conflict among experts working on controversial species: A case study on the Australian dingo. Conservation Science and Practice 5: e12900. doi: 10.1111/csp2.12900.

Ritchie, J., Skerrett, M. & Glasgow, A. (2023) Young people’s climate leadership in Aotearoa. Journal of Peace Education, 12-2023: 1-23. doi: 10.1080/17400201.2023.2289649.

Sengupta, A., Bhan, M., Bhatia, S., Joshi, A., Kuriakose, S. & Seshadri, K.S. (2024) Realizing “30 × 30” in India: The potential, the challenges, and the way forward. Conservation Letters 2024, e13004. doi: 10.1111/conl.13004.

Wang, Q., Li, X.C. & Zhou, X.H. (2023) New shortcut for conservation: The combination management strategy of “keystone species” plus “umbrella species” based on food web structure. Biological Conservation 286: 110265.doi. 10.1016/j.biocon.2023.110265.

On Ecology and Medicine

As I grow older and interact more with doctors, it occurred to me that the two sciences of medicine and ecology have very much in common. That is probably not a very new idea, but it may be worth spending time on looking at the similarities and differences of these two areas of science that impinge on our lives. The key question for both is how do we sort out problems? Ecologists worry about population, community and ecosystem problems that have two distinguishing features. First, the problems are complex and the major finding of this generation of ecologists is to begin to understand and appreciate how complex they are. Second, the major problems that need solving to improve conservation and wildlife management are difficult to study with the classical tools of experimental, manipulative scientific methods. We do what we can to achieve scientific paradigms but there are many loose ends we can only wave our hands about. As an example, take any community or ecosystem under threat of global warming. If we heat up the oceans, many corals will die along with the many animals that depend on them. But not all corals will die, nor will all the fish and invertebrate species, and the ecologists is asked to predict what will happen to this ecosystem under global warming. We may well understand from rigorous laboratory research about temperature tolerances of corals, but to apply this to the real world of corals in oceans undergoing many chemical and physical changes we can only make some approximate guesses. We can argue adaptation, but we do not know the limits or the many possible directions of what we predict will happen.

Now consider the poor physician who must deal with only one species, Homo sapiens, and the many interacting organs in the body, the large number of possible diseases that can affect our well-being, the stresses and strains that we ourselves cause, and the physician must make a judgement of what to do to solve your particular problem. If you have a broken arm, it is simple thankfully. If you have severe headaches or dizziness, many different causes come into play. There is no need to go into details that we all appreciate, but the key point is that physicians must solve problems of health with judgements but typically with no ability to do the kinds of experimental work we can do with mice or rabbits in the laboratory. And the result is that the physician’s judgements may be wrong in some cases, leading possibly to lawyers arguing for damages, and one appreciates that once we leave the world of medical science and enter the world of lawyers, all hope for solutions is near impossible.

There is now some hope that artificial intelligence will solve many of these problems both in ecological science and in medicine, but this belief is based on the premise that we know everything, and the only problem is to find the solutions in some forgotten textbook or scientific paper that has escaped our memory as humans. To ask that artificial intelligence will solve these basic problems is problematic because AI depends on past knowledge and science solves problems by future research.

Everyone is in favour of personal good health, but alas not everyone favours good environmental science because money is involved. We live in a world where major problems with climate change have had solutions presented for more than 50 years, but little more than words are presented as the solutions rather than action. This highlights one of the main differences between medicine and ecology. Medical issues are immediate since we have active lives and a limited time span of life. Ecological issues are long-term and rarely present an immediate short-term solution. Setting aside protected areas is in the best cases a long-term solution to conservation issues, but money for field research is never long term and ecologists do not live forever. Success stories for endangered species often require 10-20 years or more before success can be achieved; research grants are typically presented as 3- or 5-year proposals. The time scale we face as ecologists is like that of climate scientists. In a world of immediate daily concerns in medicine as in ecology, long-term problems are easily lost to view.

There has been an explosion of papers in the last few years on artificial intelligence as a potentially key process to use for answering both ecological and medical questions (e.g. Buchelt et al. 2024, Christin, Hervet, and Lecomte, 2019, Desjardins-Proulx, Poisot, & Gravel, 2019). It remains to be seen exactly how AI will help us to answer complex questions in ecology and medicine. AI is very good in looking back, but will it be useful to solve our current and future problems? Perhaps we still need to continue training good experimental scientists in ecology and in medicine.  

Buchelt, A., Buchelt, A., Adrowitzer, A. & Holzinger, A. (2024) Exploring artificial intelligence for applications of drones in forest ecology and management. Forest Ecology and Management, 551, 121530. doi: 10.1016/j.foreco.2023.121530.

Christin, S., Hervet, É. & Lecomte, N. (2019) Applications for deep learning in ecology. Methods in Ecology and Evolution, 10, 1632-1644. doi: 10.1111/2041-210X.13256.

Desjardins-Proulx, P., Poisot, T. & Gravel, D. (2019) Artificial Intelligence for ecological and evolutionary synthesis. Frontiers in Ecology and Evolution, 7. doi: 10.3389/fevo.2019.00402.

On Critical Evaluation in Ecology

Science proceeds by “conjecture-and-refutation” if we agree with Karl Popper (1963). There is a rich literature on science in general and ecological science in particular that is well worth a series of graduate discussions even if it is pre-2000 ancient history (Peters 1991, Weiner 1995, Woodward and Goodstein 1996). But I wish to focus on a current problem that I think is hindering ecological progress. I propose that ecological journals at this time are focusing their publications on papers that present apparent progress and are shedding papers that are critical of apparent progress. Or in Popper’s words, they focus on publishing ‘conjecture’ and avoid ‘refutation’. The most important aspect of this issue involves wildlife management and conservation issues. The human side of this issue may involve personal criticism and on occasion the loss of a job or promotion. The issue arises in part because of a confusion between the critique of ideas or data and the interpretation that all critiques are personal. So, the first principle of this discussion is that I discuss here only critiques of ideas or data.

There are many simple reasons for critiques of experimental design and data gathering. Are the treatments replicated, are the estimates of data variables reliable and sufficient, are proxy variables good or poor? Have the studies been carried out long enough? All these critiques can be summarized under the umbrella of measurement reliability. There are many examples we can use to illustrate these ideas. Are bird populations declining across the globe or locally? Are fisheries overharvesting particular species? Can we use climate change as a universal explanation of all changes in wildlife populations? Are survey methods for population changes across very large areas reliable? The problem is tied into the need for good or bad news that must be filtered to the news media or social media with high impact but little reliability. 

The problem at the level of science is the temptation to extrapolate beyond the limits of the available data. Now we come to the critical issue – how do our scientific journals respond to critical reviews of papers already published? My concern is that in the present time journals do not wish to receive or accept manuscripts that are critical of previously published papers. These decisions are no doubt confidential for journal publishers. There is perhaps some justification for this rejection policy, given that in the few cases where critiques are published on existing papers, the citation score of the original paper may greatly exceed that of the critique. So, conjecture pays, refutation does not.

Journals are flooded with papers and for the better journals I would expect at least a 60-80% rejection rate. For Science the rejection rate is 94%, for Nature 92%, and for the Journal of Animal Ecology 85% of submitted manuscripts are rejected. Consequently, the suggestion that they reserve space for ‘refutation’ is too negative to their publication model. There is little I can suggest if one in caught in this dilemma except to try another less premium journal, and remember that web searches find papers easily no matter where published. If you need inspiration, you can follow Peters (1991) and write a book critique and suffer the brickbats from the establishment (e.g. Nature 354: 444, 12 December 1991).

But if you are upset about a particular paper or series of papers, remember critiques are valuable but follow these rules for a critique:

  1. Keep it short, 5 typed pages should be near maximal length.
  2. Raise a set of major points. Do not try to cover everything.
  3. Summarize briefly the key points you are in agreement with, so they are not confounded in the discussion.
  4. Discuss what studies might distinguish hypothesis A vs B, or A+B vs C.
  5. Discuss what better methods of measurement might be used if funding is available.
  6. Never attack individuals or research groups. The discussion is about ideas, results, and inferences.

Decisions to accept some management actions may have to be taken immediately and journal editors must take that into consideration. Prognostication over accepting critiques may be damaging. But all actions must be continually evaluated and changed once the understanding of the problem changes.

There are too many examples to recommend reading about past and present controversies in ecology, so here are only two examples. Dowding et al. (2009) report a comment on suggested methods of controlling introduced pests on Macquarie Island in the Southern Ocean. I was involved in that discussion. A much bigger controversy in Canada involves Southern Mountain caribou populations which are in rapid decline. The proximate explanation for the decline is postulated to be predation by wolves and thus the suggested management action is shooting the wolves. Johnson et al. (2022), Lamb et al. (2022) and Superbie et al. (2022) provide an entre into this literature and the decisions of what to do now and in the future to prevent extinction of these ungulates. The caribou problem is complicated by the interaction of human alteration of landscapes and the natural processes of predation and food availability. Alas nothing is simple.

All these ecological dilemmas are controversial and the important role of criticism involving evaluations of alternative hypotheses are the only way forward for ecologists involved in controversies. In my opinion most ecological journals are not doing their part is publishing critiques of the conventional wisdom.

Dowding, J.E., Murphy, E.C., Springer, K., Peacock, A.J. & Krebs, C.J. (2009) Cats, rabbits, Myxoma virus, and vegetation on Macquarie Island: a comment on Bergstrom et al. (2009). Journal of Applied Ecology, 46, 1129-1132. doi: 10.1111/j.1365-2664.2009.01690.x.

Johnson, C.J., Ray, J.C. & St-Laurent, M.-H. (2022) Efficacy and ethics of intensive predator management to save endangered caribou. Conservation Science and Practice, 4: e12729. doi: 10.1111/csp2.12729.

Lamb, C.T., Willson, R., Richter, C., Owens-Beek, N., Napoleon, J., Muir, B., McNay, R.S., Lavis, E., Hebblewhite, M., Giguere, L., Dokkie, T., Boutin, S. & Ford, A.T. (2022) Indigenous-led conservation: Pathways to recovery for the nearly extirpated Klinse-Za mountain caribou. Ecological Applications 32 (5): e2581. doi: 10.1002/eap.2581.

Peters, R.H. (1991) A Critique for Ecology. Cambridge University Press, Cambridge, England. 366 pp. ISBN:0521400171.

Popper, K.R. (1963) Conjectures and Refutations: The Growth of Scientific Knowledge. Routledge and Kegan Paul, London. 412 pp. ISBN-13: 978-0415285940.

Superbie, C., Stewart, K.M., Regan, C.E., Johnstone, J.F. & McLoughlin, P.D. (2022) Northern boreal caribou conservation should focus on anthropogenic disturbance, not disturbance-mediated apparent competition. Biological Conservation, 265, 109426. doi: 10.1016/j.biocon.2021.109426.

Weiner, J. (1995) On the practice of ecology. Journal of Ecology, 83, 153-158.

Woodward, J. & Goodstein, D. (1996) Conduct, misconduct and the structure of science. American Scientist, 84, 479-490.