Getting quantitative & testing Island Biogeography Theory

Ecological theories and breakfast cereal naturally go hand in hand, at least for us Conservation Science folks. We have a tradition of using cereal for scientific experiments (check out our results from 2015 and 2016), testing MacArthur and Wilson’s Island Biogeography Theory, and some of us among the teaching staff have been known to play “Guess the theory” during breakfast – a stimulating start of day putting your ecological knowledge to a test!


This Tuesday morning, though, there was no question as to which theory we are referring to – Island Biogeography, and in particular the ideas that the bigger an island is, the more species it can support, and the more isolated an island is, the less species it will be colonised by. The premise of our experiment is simple. While in our usual day to day lives it may be true that no man is an island, for the purpose of this experiment, everyone was indeed an island, or at least they owned one. Each student grabbed a container of a particular size and placed it at a random distance from the “mainland”. We then temporally abandoned our islands, returned to the mainland, which happened to be supporting a great abundance of cereal species. With hands full of cereal and lined up along the mainland, we turned our backs to our islands, and threw the cereal in their direction.

We measured, counted, set out our hypotheses, and then went through a quick coding exercise to unwrap the data presents!


Fig. 1.  Species-area and species-isolation relationships presented using different analytical approaches.

Our data were quite zero-inflated as you can see from the first set of plots above. Overall, there was a trend for more species on bigger islands, and less species on more isolated islands. After seeing the plots, we discussed how we can improve our cereal experiment in the future. Perhaps we should have used more cereal and repeated our colonisation processes a few times to increase our sample size, and it probably didn’t help that we were colonising our islands as hurricane Ophelia was passing through the UK – the winds could have carried away our cereal species in unpredictable directions. Most of the students chose small containers, so we had few data points for islands with large areas. On the third plot above, which we made by fitting a smooth curve,  you can spot an interesting hump-shaped species-isolation relationship. Well, we think we know why! Our islands may have been a bit too close to the mainland, so when we threw the cereal in the air, it would fly over the closest islands and be more likely to land in the islands at an intermediate distance.

Fig. 2. Species-area (A) and species-isolation (B) relationships for brown and white species.

Our cereal species came in different colours – brown and white, but colour didn’t seem to affect the species-area and species-isolation relationships.

We wrapped up our morning of island hopping with another visit to the mainland, with our metaphorical mainland being Kluane National Park this time. We then took the roles of conservation scientists, tasked with estimating the size of the local brown bear population. Our resources were limited – a box of cereal, a tupperware container, a marker and our minds. Working in small groups, we designed a mark-recapture experiment. Here are the results:

Fig. 3. Population estimates of the brown bear population in Kluane National Park in Canada. Numbers derived using a mark-recapture technique and cereal as a proxy for bears. Black dots indicate actual population numbers. Error bars show standard deviations for Isla and Gergana’s groups, and standard errors for Mariana’s group.

We discussed experimental design, as well as its implications – for example Pedro and Zac’s groups didn’t calculate a measure of uncertainty around their estimates, and Gergana’s group ate their cereal, so they couldn’t count the actual population. Mariana’s group got the most accurate answer, and the first method Gergana’s group used led to the most precise estimate. The first method Gergana’s group used was to mark only 20 individuals, then for their second method, they marked 40, thinking that as more individuals are marked, the estimates become more precise, not the case this time though!

You can download the data we collected during this week’s ConSci session here – Island Biogeography dataset and Bear population dataset.

You can download our R Script here.

Keen to learn more about coding, models and data visualisation? Here are a few relevant Coding Club tutorials:

By Gergana


The Cons. Sci. 2016 field trip

We had a great year of Conservation Science in 2016.  Below you can revisit some of the highlights on our 2016 field trip to the Cairngorms.

Thanks to CairnGorm Mountain, the Glen Feshie and Rothiemurchus Estates, Badaguish Outdoor Centre and Cairngorm National Park for allowing us to visit and discuss conservation in Scotland’s mountain wilderness.

Our field trip to the highlands of Scotland has been immortalized as a video on the Teaching Matter’s website.

Here are some beautiful photos of the field trip taken by Sandra Angers-Blondin our official field trip photographer.

New Zealand and 1080: A toxic romance?

By Rebecca

New Zealand (NZ) provides a home to some of the most interesting birdlife in the world. This is because NZ is an island, which means it has allowed for unusual evolutionary processes. Humans only arrived on the island about 800 years ago. So, birds have been able to reproduce and evolve to their surroundings without human influence and without land animals trying to eat them! Since NZ is made up of island and not attached to large landmasses, the species that evolved there are only found in NZ. This makes them all the more special and important. Native birds still hold particular significance to the Māori people (first people to inhabit NZ) due to their significance in kōrero tuku iho (legends/mythology). In this present day, many of these native birds have become extinct or are now in danger of extinction due to human arrival on the islands.

Extinct bird species can be explored at . Find out more about current living species in New Zealand at .


The laughing owl, now extinct, photographed some time between 1889 and 1910. Photo: Henry Charles Clare Wright, via


The Kea, a native bird of New Zealand, which is now classed as ‘vulnerable’. Photo: David Spiegel,

Humans introduced mammals on purpose and also by accident to NZ. This is one of the biggest threats to the native bird species of NZ (PCE, 2011). Ships coming from other countries brought rats by accident, the brushtail possum as well as stoats made it to the island and began to reproduce and spread. When the mammals came, the birds were unprepared, as they have been used to living their lives without these predatory mammals. It has been estimated that 60% of all kiwi chicks are eaten by stoats (PCE, 2011). The NZ government decided something must be done to stop the decline of native bird species.

The ‘Predator Free New Zealand 2050’ action plan has been put into effect, aiming to remove the three main predators (rats, possum and stoats) from NZ by 2050. The main method of doing this is to distribute a poison called sodium fluroacetate, also known as 1080, over target areas in the hope that the predators will eat the poison (PCE, 2011). Planes currently drop the poison over these areas with little or no aim. This poison is not a specific poison for these mammals; it affects almost all breathing organisms.

This is the cheapest way of controlling the pests but the numbers of native bird species are still in decline. 1080 has been able to decrease possum numbers by 99.5% in one area (Greene, 2013). However, it is difficult to know how 1080 is affecting the wider ecosystem and if the deaths of non-target species outweigh the benefits of reducing the number of target species. It has been argued that the birds will be unable to recover from the significant declines in non-target species. A disturbance of this scale has the potential to decrease the endangered birds likelihood of thriving (Greene 2013).


The reality of distributing 1080 poison. Cartoon: Al Nisbet, 2008. Alexander Turnbull Library. NZ Cartoon Archive. DCDL-0007273. Via

There are multiple questions that need to be addressed when making decisions to continue distributing 1080. It is still unknown how the poison is affecting soils, plants and nutrients. These would be classed as ‘sub-lethal’ harms, which have not yet been investigated (Weaver, 2006). Everything in the ecosystem is interconnected and so it is essential that the sub-lethal effects of 1080 be further investigated to understand how it will affect the ecosystem as a whole. In addition to this native people of New Zealand (Māori people) rely on the bush for many reasons, one being medicine from Te Rongoā plants. It is impossible to know the effects 1080 will have on these plants in the future.

The cost of distribution would almost double if 1080 was to be distributed by the land rather than by aerial drop (PCE, 2011). However, this method would allow for a reduction in non-target species death. Unfortunately, the reduced cost and the ease of distributing 1080 by aerial drop are currently outweighing the benefits of this option for the decision makers.

The points outlined in this blog aim to communicate the significant number of discrepancies found in the thinking behind distributing 1080 across NZ. It is essential to understand how 1080 is going to affect the ecosystem as a whole, which could directly affect the lives of Māori people that rely on the services such as medicine from the bush.  Until the effects are fully understood, all distribution of the poison should be halted. The release of such a toxic substance with such little knowledge of the true effects is reckless and could worsen the situation it is aiming to better.

For further reading please see the following:

Socolar, S. and Wilcove, D. (2016). “Threatened Birds” Encyclopedia of Biodiversity. Second Edition addresses the wider scope of threatened bird species and so gives an overview of other issues bird communities are facing as well as ways of preventing these declines.

The New Zealand Department for Conservation webpage on 1080 poison.

1080: the facts offers some different views on the issue.


  1. Greene, T.C., Dilks, P.J, Westbrooke, I.M, Pryde, M.A. (2013). Monitoring selected forest bird species through aerial application of 1080 baits, Waitutu, New Zealand. New Zealand Journal of Ecology, Vol.37, No.1
  2. Parliamentary Commissioner for the Environment, PCE. (2011). Evaluating the use of 1080: Predators, poisons and silent forest. Parliamentary Commissioner for the Environment (Dr. Jan Wright) Report. Accessed online:
  3. Weaver, S. (2006). Chronic Toxicity of 1080 and its Implications for Conservation Management: A New Zealand Case Study. Journal of Agricultural and Environmental Ethics, 19(4), 367-389

Artificial Reefs: the last wave of hope for our ocean?

By Heather

2016: A tragic year for coral reefs.

The Great Barrier Reef experienced its worst ever coral bleaching event to date (1). Corals worldwide are declining along with the sea creature communities they support. Many will have heard of the phenomenon of coral bleaching. It occurs when corals become stressed and expel their algae (the organisms they live and interact with which give them their colour). It comes as no surprise that humans are the source of this issue; both directly, through harvesting and disturbing these areas, or indirectly, through climate change, which is warming the oceans to a temperature that the many corals can no longer handle (2).

Humans are also their own victims of this underwater catastrophe. Not only do we benefit economically from the biodiversity of reefs, they offer coastline protection, food, medicine and recreation (3). Vast areas which, not long ago, were vibrant, colourful undersea communities supporting around one third of marine species have transformed into desolate, grey dead zones. Further, 75% of remaining reefs are under threat (2).


Bleaching process of a coral reef near American Samoa. Photo: XL Caitlin Seaview Survey, via the Huffington Post

There is no escaping this grim reality. But all hope for reefs has not yet vanished entirely.  Actions are being taken to repair the damage.

During the 2016 Conservation Science Conference, Amy Kerr introduced us to a conservation tool that has been used for several years: Artificial Reefs. However, their effectiveness is currently being questioned.

At first glance, ‘faking it’ is surely a plausible solution to this problem. If humans have caused the loss of these magnificent structures, surely they can utilise their resources to aid their recovery.

Several types of artificial reef are currently in place:

  1. Manmade reefs are specifically designed to attempt to accurately reflect real coral reefs. Below is a ‘reef ball’, widely considered to be a successful at recolonising marine communities. However these present dangers to humans and may be disruptive to the surrounding environment (4).


Photo: TA Marine Science

2. Discarded structures such as ships or tires are a popular form of artificial reef, which are known to become home to a diverse community to organisms. Environmentalists, however, have concerns that these structures can leach toxic substances into the water, and therefore do more harm than good to marine life (5).


Photo: Richard Whitcombe, Shutterstock

3.Underwater Art Museums are a recent concept. They are manufactured to attract corals thereby combining culture with conservation. If these are successful, it is a possibility that it could raise awareness and dissuade divers from disturbing natural reefs. Take a look at this stunning video displaying exhibition by English Artist Jason DeCaires Taylor, who uses the human form to try and strengthen the connection between humans and the environment (6).



But…Is there a limit to how well we can replicate the intricacy of nature? Should we focus precious marine conservation funding on this somewhat idealistic concept? Artificial reef opponents believe it is a waste of resources. There are concerns they will fail to develop new communities of marine organisms and instead attract and displace fish from other areas. These new structures may also attract fishing in areas which already suffer from depleted stocks (7).

Amy remains optimistic and convincingly concluded that research into creating the most effective designs of reefs is crucial and focus must be placed on enhancing their long term success. In order to succeed, she suggested that regulations must be put in place in terms of fishing, water use and materials used to construct these reefs.

Time is running out, and if this is not done carefully and efficiently, the days for our remaining coral reefs will be numbered.

It is the worst of times but it is the best of times because we still have a chance.”– Sylvia Earle, Marine Biologist


  1. Authority GB. Interim report: 2016 coral bleaching event on the Great Barrier Reef.
  2. Burke L, Reytar K, Spalding M, Perry A. Reefs at risk revisited. 2011.
  3. Brander LM, Van Beukering P, Cesar HS. The recreational value of coral reefs: a meta-analysis. Ecological Economics. 2007 Jun 15;63(1):209-18.
  4. Proposal for Reef Ball Submerged Breakwater [Internet]. 2016 [cited 17 November 2016]. Available from:
  5. Sherman RL, Spieler RE. Tires: unstable materials for artificial reef construction. WIT Transactions on Ecology and the Environment. 2006;88:215-23.
  6. Underwater Sculpture by Jason deCaires Taylor [Internet]. Underwater Sculpture by Jason deCaires Taylor. 2016 [cited 17 November 2016]. Available from:
  7. Abelson A. Artificial reefs vs coral transplantation as restoration tools for mitigating coral reef deterioration: benefits, concerns, and proposed guidelines. Bulletin of Marine Science. 2006 Jan 1;78(1):151-9.

Trophy hunting in Africa: Are we killing conservation?

By Beth Hanlon

We all remember Cecil the Lion, and the debate that erupted about trophy hunting upon his death. In July 2015 Walter Palmer shot and killed Cecil with a bow and arrow, after paying $54,000 for a hunting permit in Zimbabwe. There was worldwide anger over his death, with celebrities and wildlife organisations protesting his death and the practice of trophy hunting. The controversy caused some countries to change their hunting laws, and some airlines to ban the transportation of hunting trophies.


Walter Palmer (left) shot Cecil with a bow and arrow. Photograph: Rex Shutterstock, via the Guardian.

Trophy hunting is the practice of hunting wild animals for recreation, and keeping a part of the animal as a sign of the success of the hunt. Regardless of the moral aspect of trophy hunting, there is fierce debate around the conservation benefits hunting provides.

The benefits and consequences of trophy hunting for conservation were recently evaluated by Justin Rogers during the midterm conservation science conference. Justin weighed the pros and cons of trophy hunting in Africa and its impact on conservation.

Trophy hunting is practiced in many African countries and in sub-Saharan Africa there are positive and negative examples of the effect of trophy hunting on conservation.

Trophy hunting provides benefits for communities in areas such as education, employment, income, and meat provisioning. A 2006 paper estimated gross revenues of $201 million from hunting in sub-Saharan Africa.  This financial incentive can increase wildlife conservation, as long as hunting quotas are set correctly and adhered to. One study found that rigorous management of trophy hunting areas can make them valuable conservation zones for large herbivores.

Trophy hunting generates higher revenues and has a lower environmental impact than photo-tourism. If this money makes it into the community then locals will not have to supplement their income through illegal poaching, thus helping conserve the wildlife. Hunting can be the only viable land-use in vast areas, and can preserve the ecosystem when other forms of tourism, such as photo-tourism, cannot.

Other than the obvious ethical issues of killing large animals for fun, there are other arguments against trophy hunting. The benefits from hunting for local communities do not always materialise, or are not always shared equitably among the community. In areas with poor management, and quotas that are not set properly, hunting can be unsustainable and damaging to the animal populations. Under current hunting rates in southern Africa trophy bull elephants will be removed from the population in less than 10 years.

Hunting selective individuals of a population (usually the largest) can result in undesirable evolutionary consequences, and changing population demographics. Trophy hunting has been shown to change the entire evolutionary path of bighorn sheep, which are hunted in North America for their large horns. Over time, ram body weight and horn size has declined significantly. There is a lack of research and data about the impact of trophy hunting, on which assessments can be made to inform management strategies.


Photo-tourism can generate high revenues and promote wildlife conservation. Photograph: Ralph Lee Hopkins, National Geographic Stock

Justin states that trophy hunting should be assessed on a case-by-case basis, and that the management should be guided by the total benefit for conservation. In an African context this conservation benefit is the net benefit of trophy hunting on wildlife populations, ecosystems, biodiversity, and local communities. If trophy hunting has a larger net benefit than photo-tourism, then a management plan should be devised to maximise this benefit. If photo-tourism has a higher net benefit, then trophy hunting can be avoided.

Hopefully, with proper management of trophy hunting areas, wild animal populations can be conserved for future generations to enjoy, and for the Earth to remain a little bit wilder.

Deer control and reforesting: the missing lynx?

By Joe

Considering the ragged state of Scottish forests1, many people point the finger at deer2-3. While human activity and overharvest shrunk Scotland’s forest cover, deer have prevented much of it from recovering4. The last British wolf was killed in the 17th century4, and since then deer have lacked natural predators, only being eaten as venison. With populations no longer kept in check, their numbers have exploded5, and our forests are feeling the impact.

Deer are flexible herbivores who eat all kinds of vegetation, and lots of deer need lots of food. Deer stop forests from regenerating because they eat the youngest shoots, which can’t then mature into adult trees tough enough to protect themselves. With few deer, enough seedlings escape to continue the forest, but with too many deer almost every shoot is eaten. The future of Scottish forests lies in deer control, and stalking alone isn’t enough.

The least intensively managed way to control deer, and invigorate our forests, would be to rectify the mistakes of medieval hunters and reintroduce our large predators. One predator which could be reintroduced to current forests is the lynx, and the Lynx UK Trust have developed a proposal for exactly that6.

They plan to release and monitor twelve adult lynx, to see whether the environmental effects are what we expect. The plan has been opposed by farmers, who worry about lynx predating livestock, as happens in Norway, but this is largely due to negligent Norwegian shepherds grazing sheep in the forest7, banned under UK farming subsidy.


(Photo: Lynx UK Trust)

Lynx predate mostly on roe deer, one of the Scotland’s most common species5, but also take fallow and sika. Sika deer are non-native and particularly hard to stalk as they prefer particularly dense woodland. Only red deer are too large for lynx, but these are the most sought-after for meat and stalking, so can be viably controlled otherwise until larger predators are reintroduced.

If lynx reintroduction is successful in the UK, it paves the way for other reintroductions. With these, we may eventually attain a self-regulating ecosystem containing some aspect of the rich flora and fauna our ancestors cleared centuries ago. Many organisations are working towards this in Scotland, for more information ‘Rewilding Britain’ ( and ‘Trees For Life’ ( are two excellent places to start.


  1. Rudel, T. K., Coomes, O. T., Moran, E., Achard, F., Angelsen, A., Xu, J., & Lambin, E. (2005). Forest transitions: towards a global understanding of land use change. Global environmental change, 15(1), 23-31.
  2. Putman, R. J. (1996). Ungulates in temperate forest ecosystems: perspectives and recommendations for future research. Forest Ecology and Management, 88(1), 205-214.
  3. Côté, S. D., Rooney, T. P., Tremblay, J. P., Dussault, C., & Waller, D. M. (2004). Ecological impacts of deer overabundance. Annual Review of Ecology, Evolution, and Systematics, 113-147.
  4. Rackham, O. (1986). The History of the Countryside. JM Dent and Sons, London.
  5. Edwards, T., & Kenyon, W. (2013) SPICe Briefing: Wild Deer in Scotland. Scottish Parliament, Edinburgh.
  6. Eagle, A., & Chance, C. (2015) Lynx UK Trust’s Proposal for a trial reintroduction. Launceston, Cornwall: Lynx UK Trust.
  7. Odden, J., Linnell, J. D., Moa, P. F., Herfindal, I., Kvam, T., & Andersen, R. (2002). Lynx depredation on domestic sheep in Norway. The Journal of wildlife management, 98-105.



By Aoife Hutton


The concept of rewilding has recently emerged as a hot topic in both scientific and public spheres. Championed by the writings of George Monbiot in his book ‘Feral and popular TED talk, rewilding pushes the bounds of a previously a conservative approach to conservation science and encourages us to reassess our goals, and aim big.

Rebecca McDonald, a 4th year ecological and environmental science undergraduate at University of Edinburgh, last week presented a project on the aims, scope and logic of a potential rewilding effort in North America proposed by Donlan et al., (2005). Rebecca’s project was refreshingly critical in scrutinizing just how realistic the often times romaticised concept of rewilding actually is.

Donlan et al. proposed that rewilding should aim to restore ecosystem function of the Pleistocene era and reintroduce megafauna lost 13,000 years ago – a time long before human arrival in North America. In particular, this would mean refilling the niche once taken by proboscidians (mammoths, mastadons and gomphotheres). Modern day relatives most similar are the Asian and African elephants. As idyllic as elephants roaming along the edges of Route 66 may sound, there are some pretty mammoth logistical issues involved.


How would elephants be transported to the US? How would elephants react to a vegetation they have not evolved to live with? What impact would human-elephant interactions and conflict have? And for the economists among, how much would all of this cost?

Alongside these quite obvious concerns, maybe it is time to address the elephant in the room about Pleistocene rewilding; if the aim is to restore ecological function of a pre-human time, how do we, as humans, co-exist?

The fundamental separation of human and non-human animals inferred (perhaps albeit unintentionally) by this kind of rewilding scheme is problematic on several levels. If we aim to restore ecological function to a time before human existence in an area, how do resolve the fact that humans do and have been living in those areas for many generations.

Sadly, conservation has been an oppressive force to indigenous people – one just has to look at the displacement of Native American people from tribal land for the creation of National Parks in the US as an example. While rewilding North America wouldn’t necessarily lead to similar circumstance, the cultural and social implications of such a project definitely need to be examined more thoroughly to address such concerns.

Not all rewilding projects have a Pleistocene era as the end-sight, and countless projects have shown the success of rewilding, delivering the top-down benefits to ecosystems which advocates of the concept endorse. Taking a more recent point in geological time as the aim seems to prove for a more attainable result, one such case was the reintroduction of wolves in Greenstone National Park, US, which had been lost from the area less than 100 years prior. The reintroduction achieved expected and desirable top down changes to the ecosystem, restoring beaver populations and ultimately affecting river hydrology.

While some rewilding efforts do seem highly effective tool in conservation science, I remain skeptical over Pleistocene era rewilding. In this case, time and resource seems better spent on looking after the flora and fauna in our presently existent biosphere, and on trying to break down barriers of the human/non-human interface, so that we can come to see ourselves as not only a cause of problems to ecosystems, but also as components which are a part of a living ecosystem – we are not above it.

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