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Counting phantoms in the forest. The role of hunters in monitoring large carnivores.

Counting phantoms in the forest. The role of hunters in monitoring large carnivores.

Author: John Linnell/Saturday, November 29, 2014/Categories: Gallery

Europe is currently home to large, and generally expanding, populations of wolves, brown bears and Eurasian lynx. Keeping track of their distribution and numbers is a task far beyond the capability of any research project. In many countries of northern and eastern Europe the hunters represent the backbone of extensive monitoring programs. The enormous effort that they often invest is one of the least appreciated partnerships in European conservation.

Very few people realize just how many large carnivores roam the European landscape. The latest estimates are of 17.000 bears, 12.000 wolves, 8.000 Eurasian lynx and 1.000 wolverines. These carnivores live in many parts of the continent, and not just in the distant mountains and deep forests. In many areas, wolves roam close to houses, towns and in agricultural landscapes. But they are rarely seen. They move like phantoms. Their ability to be invisible is probably one of the major determinants of their survival in our modern and crowded world. However, having an idea of the numbers of wild animals and whether these numbers are increasing or decreasing is a fundamental requirement for effective management and conservation. It is also a legal requirement under EU legislation. The question is often asked as to how we can count such elusive animals? The answer lies in the use of a lot of technology in some cases and a lot of manpower for all cases. In many countries, this manpower is provided by thousands of hunters who dedicate their time freely to help scientists and authorities come up with the best possible estimates for the numbers of large carnivores roaming the forests of Europe.

There are four main ways that hunters provide crucial observations for scientists to analyse. The first, involves submitting samples such as teeth (for ageing), tissue samples (for genetical and veterinary analysis) and measurements of the animals that they shoot which allow scientists to make some indirect judgments about the size, health and trend of the population. At the very least, this material allows managers to consider the impact of hunting when assessing the dynamics of populations and provides data on the distribution of the species. At the best, if a large material is collected systematically over many years it is possible to do some advanced statistical analysis to retrospectively estimate the size of populations.

The second approach avails of the recent developments in digital camera traps that record images of wild animals that walk past them. The sales of these cameras has exploded in recent years as hunters can now indulge their curiosity to see just what is happening in their hunting grounds when they are not there themselves! The result is many observations of large carnivores that can be collected and integrated into larger monitoring programs. This is particularly valuable for lynx as their spot patterns allow individuals to be recognized, which permits very accurate estimates of their numbers to be made. 

The third approach involves very low technology – simply the reporting of tracks in the snow. This is especially valuable for lynx and wolf monitoring, as it is possible for experienced observers to interpret details such as the presence of reproduction (for lynx and wolves) and pack size (for wolves). If enough observations are collected over large areas it is possible for managers to use data from modern radio-telemetry studies (that quantifies movement rates of individual carnivores) to estimate the number of animals or packs.

The final approach come straight from the pages of modern crime fighting. A scat collected in the forest can yield DNA which allows scientists to determine the sex and individual identity of the animal who deposited it in the wild. Collecting large numbers of scats, running them through the laboratory process, and doing some advanced statistics can produce very accurate estimates of the size of populatiions. At present this methodology constitutes the gold-standard for monitoring large carnivores, especially bears and wolves.

However elegant or sophisticated these analysis approaches are, they all depend on having access to networks of thousands of eyes and ears in the forest who are willing to make reports, submit photographs, or collect a piece of a scat and post it to a laboratory. Almost the entire surface area of Europe falls within some hunters hunting ground, so who better to assist?

 

In addition to helping keep track over the size and trends of large carnivore populations, the data provides the basis for much of the ecological research that is currently conducted on large carnivores and indeed for large mammals in general, in Europe. Without the enormous effort provided by hunters, it would not be possible for any research project to collect data from so many individuals, over such large areas, for so many years on these species that are logistically very challenging to study.

This partnership between hunters, scientists and managers is one of the most underappreciated alliances in modern day conservation. There is currently a lot of talk in conservation circles about "citizen science", but the collaboration between hunters and wildlife researchers / managers goes back at least 40 years in many countries. Although it is not present in all countries, this approach offers a huge potential to be spread across Europe. In essence, all it requires is some basic organization to create a system that can record the observations made by hunters in a centralized database. In a world of smartphones it is becoming increasingly easy to organize this transfer of data. There needs to be some field controls and validation procedures for observations such as tracks in the snow, but this can be solved through training of local inspectors. The use of DNA analysis from scat samples removes this issue as the lab provides the quality control by verifying the species identity. The important refinement of recent years has been the separation between data collection (by hunters) and data interpretation (by researchers or managers). This permits the use of state of the art analysis tools (both statistical and laboratory tools) and ensures objectivity and reduces bias (both real and perceived) in interpretation.

At present large carnivores are very controversial across Europe, and the debates around them are becoming increasingly polarized and politicized. Although they are likely to remain controversial for the foreseeable future the type of joint work that is represented by these examples has two main benefits. Firstly, by collecting high quality data in a participatory manner it reduces some of the uncertainty associated with the size of the populations, which means that management decisions can be made with greater agreement about  the actual status of the population. Secondly, the act of working together on a common task can help improve the perceptions that different groups have of each other, hopefully breaking down stereotypes, and permitting the development of trust and mutual respect that are so crucial for resolving any type of conflict.

Case studies

Estonia – Every year in Estonia, approximately 5000 bear, lynx and wolf site and track observations are reported by hunters to the Estonian Environment Agency, which analyses the data to separate them into different reproductive units. The data is combined with that from wolves and lynx equipped with GPS-GSM collars which provide further information on home range size and movement patterns. This combination of data is used to understand the current status and trends of large carnivore populations. Hunters also contribute by surveying up to 4500 km of transects to count wolf and lynx tracks in the snow. Finally, biological samples are provided to researchers from each bear, lynx or wolf shot

Slovenia – In Slovenia, hunters routinely report all detected mortality of large carnivores, either from legal culls or other causes, which is then verified, measured and sampled by Slovenia Forest Service (SFS) personnel. Professional hunters in SFS hunting reserves, which cover a large proportion of the prime large carnivore habitat, have also been systematically recording all signs of large carnivore presence since 1999. Since 2003 (and for a decade before that with a less strict methodology), Slovenian hunters have been systematically counting observations of brown bears over a network of 167 permanent observation sites, providing valuable data about litter sizes and population trends. These bear surveys are done tri-annually during the full moon, simultaneously over the entire area, and all bear observations are described and reported. The hunters have also been the key contributor of non-invasive samples in the 2007 genetic census of bears in Slovenia, and are expected to continue this work into the next census planned for 2015. They were also important contributors to the intensive monitoring of wolves between 2010 and 2013 (non-invasive genetic sampling, snow tracking and howling tests) within the scope of the project Life SloWolf, and will be key partners in the wolf survey planned for 2015. It is also important to remember that Slovenian hunters actually re-introduced the Dinaric lynx population in 1973, and they continue to collaborate in many monitoring and conservation activities ever since. And when it became clear that the Dinaric lynx will become extinct without assistance and that action must be taken, the Slovenian Hunters Association immediately stepped up as a partner in a population reinforcement project proposal submitted to the 2014 Life call for proposals.

Sweden - In Sweden, bears scats are collected for DNA identification during the autumn to estimate population size. This takes place in different counties for different years and almost all scats are collected by hunters. Every year many thousand scats are collected and submitted for analysis. To estimate trends and relative abundance, hunters keep track of their observations of bears and also wolf, lynx and wolverines during the autumn moose hunt. This Large Carnivore Observation Index (LCOI) is an add-on to the nationwide moose observation system and takes place during the first seven days of the moose hunt.  The result is an index of the number of observations per effort unit (observation hours) which amounts to more than 5 million hours and 1000 bear observations each year in Sweden. All bears shot during hunting are also measured and sampled for monitoring purposes. Hunters also participate in countywide snow tracking surveys of wolves and lynx, which is organized by the county wildlife management boards. 

Slovakia – Hunters have been annualy conducting their own census of large carnivores in Slovakia for many decades, but these results have been called into question  in recent years. A pilot project has been started in 2014 to bring multiple stakeholders, including hunters, together into collecting wolf scats for DNA analysis in an effort to resolve the controversy around wolf numbers.

Norway: Norwegian hunters are central to the monitoring of the lynx population. Every year several hundred observations of the tracks of female lynx accompanied by kittens are reported to ROVDATA, a national large carnivore monitoring program based at the Norwegian Institute for Nature Research (www.rovdata.no). Using data on movement rates and home range sizes collected from lynx that have been equipped with GPS collars all across Norway it is possible to interpret these observations and come up with an estimate for the number of different females who reproduced the previous summer. This measure forms the mainstay of lynx monitoring. In addition, many hunters maintain camera traps, both of their own and those belonging to researchers which provide many additional observations. Furthermore, the hunters' association are responsible for a network of almost 2000 transects that are surveyed on skis each winter to produce an index of the number of lynx tracks. Finally, all hunters who shoot a lynx submit the entire skinned carcass for research purposes.

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