Crawlers and fliers – how to study forest insects

Studying insects is interesting yet challenging. Determining individuals to the species level

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The presence of birch bark beetles can be detected by their unique eating patterns. ©Stella Thompson

nearly always requires capturing them first, although some species, such as the birch bark beetle (Scolytus ratzeburgi), can be identified by the unique pattern they leave on tree trunks. However, it is almost always necessary to use various types of traps to capture individuals if identifying the insect species present at a certain site is the main objective of a study. For example, butterflies are trapped during the night using light traps, and the occurrence of certain protected species can be confirmed using feromone traps that use synthetic lures as bait. Traps can be dug into the ground, lifted high up into tree canopies, or attached to the insides of hollow tree trunks.

As my PhD research I am assessing how beavers affect forest beetle populations. I have several research questions:  do beaver-induced flood zones have different beetle species assemblages than other areas, do the increased moisture and sunlight conditions in the flood zone affect species assemblage, and do beaver areas advance or hinder potential forest pest or protected species. My research combines a game species with widespread effects on its surroundings and forest beetles, several species of which have become scarce and require protection. Beaver-induced flooding and the species’ habit of felling tree trunks may locally disturb forest owners, but my study is looking into whether beavers’ actions facilitate or disturb forest pests. Combining game and insect research is cool, and generates new information on which to base decision-making for future protection measures, beaver population management, and even for using beavers as a natural tool for restoring degraded wetlands and forests.

Window traps are widely used for determining the insect assemblages of sites. Window traps cannot be used to capture specific insect groups, because all sorts of invertebrates ranging from flies to pseudoscorpions and wasps to beetles creep or fly into them. Window traps are very simple: the trap is attached to a tree trunk or set to hang between two trees. Insects crawl or fly into the plastic plexiglas frame and then fall through the funnel into a liquid-filled container at the bottom. The container is filled halfway with water, dishwashing fluid, and salt. The dishwashing fluid prevents the insects from regaining flight, consequently drowning them. The salt helps preserve the insects until the trap is emptied out, which happens about once a month. I have 120 traps spread out at several sites, so every summer I collect about 600 samples.

Unfortunately other creatures may sometimes end up caught in the window traps. So far I have inadvertently captured a few common lizards and a bat. This is always disappointing, because an individual dying for nothing does not advance research or science in any way. In the same way it is frustrating if you unintentionally set up a trap on a tree trunk that an ant colony uses as its route. Hundreds or even thousands of ants may drown in the window trap. As my own study focuses on beetles, I cannot utilize the ants in any way. At least this does not happen very often.

After the trap container has been emptied the gathered sample is sifted through using tweezers and a microscope, to separate the insect groups that I am interest in. Next the individuals are determined to the necessary level. Sometimes determining the family level is enough, but if making conservation decisions or gaining new information on certain species is the goal, it is usually necessary to determine individual insects to the species level. How this is done depends on the order in question, e.g. beetles are often recognized by their ankles and genitals.

Occasionally you come across data deficient species, i.e. species that are not well known or understood. Species, genera, and families are determined using identification keys, which are sometimes incomplete. For example, currently the best key for identifying Finnish rove beetles is in German, and for several families the most complete keys are in Russian. So I’m currently kind of happy that I studied German in middle and high school. I guess next I should begin uncovering the secrets of Russian vocabulary.

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What if species conservation leads to conflict?

The rise of nature conservation during the last century was a response to the weak environmental situation. Many animal species were declining, and conservationists strove to save them from extinction. Protection has worked for several species and population numbers have grown. This is obviously a good thing for the species, but can conservation offer an answer, if protection leads to conflict?

© Sari Holopainen

Barnacle geese have damaged e.g. Helsinki university research fields © Sari Holopainen

Big bird conflicts

Geese were the first group that I encountered this problem with. Many geese species have been strictly conserved due to population decreases. For some species conservation has worked so well that population increases have exceeded the tolerance limits of farmers. I read a text discussing the flexibility of conservation and management: if conservation targets are achieved, are we able to modify conservation-based management, if this is possible?  Geese-induced crop damages in particular have increased, and now geese also cause problems in cities. The populations of whooper swans and cranes have also increased in Finland, and they have caused crop damage. The conflicts between birds and farmers have been solved by paying farmers compensations, but other arrangements should also be utilized in the long term. One method is to attract for example cranes to certain fields, where they do not cause uncontrollable damage. When it comes to game species, the relationship between conservation and hunting should be considered. For example, legalizing the hunting of barnacle geese has been suggested in Finland, but is currently not realized. On the contrary, barnacle geese can be hunted to prevent crop damages in neighboring Estonia.

Eider breeding is in trouble © Sari Holopainen

Eider breeding is in trouble © Sari Holopainen

Even a protected predator eats meat

The dilemma becomes especially difficult when the protection of one species leads to a conflict in the protection of another species. Such a situation can evolve for example between a prey and its predator. Saving the white-tailed eagle from extinction in Finland is one of the great success stories of Finnish nature conservation. However, according to new research, eagles are one reason why eider populations have declined in the Finnish archipelago. Due to predation some islands have effectively lost their entire nesting eider populations. Eagles also utilize eider broods swimming at sea. However, the effect of the eagle is not so simple: on the other hand eagles control the American mink, which is an extremely harmful alien species destroying eider nests. In addition to eagles, eiders are also threatened by the eutrophication of the Baltic Sea and ecosystem changes connected to salt rate changes. If the eider population continues to decline, managers must evaluate the hunting possibilities of this traditional game species, although it might be not enough to solve the complicated problems facing the species.

A conflict situation has also appeared between the wolf and Finnish forest reindeer, both endangered species. There are only two populations of forest reindeers in Finland occurring in Kainuu and Suomenselkä. The growth of the Kainuu population has ceased after an increase of the wolf population in the area. Calf production has dropped, some of the traditional production areas are now empty, and the most important reason for the death of collared female forest reindeer is wolves. But as with the eider, changes have also occurred in the environment of the forest reindeers. Due to forest industry, forests are becoming younger, which has a positive effect on the moose, thus supporting dense wolf populations. As a result the forest reindeer suffers:  younger forests are not an optimal habitat for the species, and they suffer more from predation because moose is the more common species.

Calf mortality is observed to be worryingly high in Kainuu forest reindeer population. Calf  in Korkeasaari Zoo in Helsinki © Sari Holopainen

Calf mortality is observed to be worryingly high in Kainuu forest reindeer population. Calf in Korkeasaari Zoo in Helsinki © Sari Holopainen

Trees form a forest

These are good examples of how the protection of one species can be surrounded by complicated ecological impacts, not even to mention human dimensions. These connections should be considered when planning conservation. The question becomes especially timely if protection is successful. The conversation around conservation issues (at least for me) fairly often appears as straightforward, where risks and threats are recognized, but these complicated impacts could be more underlined. What to do if one species begins threatening another, or when a population increase causes damages? Are we able to understand the entire situation and work with the whole palette of tools available to reach the best conclusion, or do we just slide into polarized debate with no constructive solutions to offer? One example of such creative management issues occurs in Finland, where wolf hunting is currently allowed to increase the value of the wolf as a game animal. Concurrently it is hoped that attitudes towards the wolf will become better and wolf poaching will decrease. We are currently waiting for the results of this experiment.

Wolf population management – problems in every direction

The wolf is currently quite the hot potato in Finland. In fact, wolves are such a burning topic, that finding neutral information on the current state of the species and on hunting it can be difficult.

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Wolf pup in Polar Park, Norway. © Sari Holopainen

Wolves form packs of several individuals to optimize their ability to hunt moose and deer, their staple food. A pack is run by an alpha pair, or a male and female wolf that have mated for life. The other individuals in a pack do not produce offspring, and young individuals may wander between packs to find mates or raise their position in the hierarchy. Alpha pairs are what keep a pack together.

The wolf is designated an endangered (EN) species in Finland, and strictly protected in the European Union (EU). The Finnish wolf population grew during the early 2000s, due to increased protection and additional individuals moving in from Russia. This increased both the incidence of damage caused by wolves (e.g. to hunting dogs) and the number of wolf sightings around human habitation, leading to dissatisfaction in wolf conservation measures and increased poaching. The wolf population began declining in 2007 due to widespread poaching, which in turn angered conservation organizations and the EU. Since then the wolf population size has seesawed back and forth, and confrontations between various interest groups have escalated.

To alleviate the wolf conflict, the Finnish Ministry of Agriculture and Forestry decided to implement a two-year trial wolf hunt in 2015–2016, aimed to control the population. The effects of the cull will be evaluated after this period. The trial cull is based on a wolf management plan, which attempts to incorporate both the requirements of people living in wolf territory and that of wolf conservation. The management plan is territory-based, meaning all actions are planned per wolf pack and territory.

The management plan determines the smallest viable wolf population as 25 breeding pairs. The Natural Resources Institute Finland (Luke) will produce an estimate for the country’s total wolf population, and based on this evaluation the Ministry determines the largest yearly quota that can be culled using population control permits. However, this quota does not automatically have to be reached.

Population control permits are granted for hunting young individuals, which most likely have the smallest impact on the vitality of a pack. These permits can also be granted for hunting problematic individuals that e.g. repeatedly enter yards or come close to humans. Population control permits can only be granted to target wolf packs that produce litters, or in special conditions on packs in areas where the species has a stronghold. In addition to population control permits, wolves can also be hunted with special permits granted for damage control or by law enforcement. These two permit types are granted only when dealing with problem wolves.

Wolf population fluctuations and management will continue to cause problems in the future. Various interest groups have lost trust in each other and in the Ministry’s wolf management plan. Accommodating both the protection and management of an extremely endangered top predator is very difficult in a situation where said species also causes damage to and fear in certain interest groups. Additionally, protecting the Finnish forest reindeer (Rangifer tarandus fennicus), another extremely endangered species, requires straightforward action plans in terms of the wolf. Population levels of the Finnish forest reindeer are believed to have suffered because of the dense wolf population in the district of Kainuu.

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Wolf in Polar Park, Norway. © Sari Holopainen

The complete protection of the wolf, a management regime in practice at the beginning of the 2000s, obviously failed to work. The population grew initially, but was quickly bulldozed by unsustainable poaching. The population decreased up to 15% a year between 2006 and 2010. The population was approximately 250–270 individuals at the end of 2006, but by the end of 2007 the level had dropped to 200. Complete protection of the species crossed a line in Finnish society, after which poaching was used as an excuse for preventing future damage – a situation that should not be allowed to form. Returning to a similar conservation model would require intensive intervention to stop poaching.

The two-year trial cull was completed at the end of February. Luke evaluated the Finnish wolf population at 220–245 individuals prior to the trial period in 2015. Two hunting seasons later, in March 2016, population levels were estimated at 200–235 individuals. When looking solely at these numbers, the cull has managed to keep the population fairly level. However, 43 wolves were shot during the two-year cull, and over half of these (24) were over two-year-old individuals. It is easy to see that the cull has not met its goal of only targeting young individuals. In fact, a staggering 21% of the culled individuals were alphas. And this level may still increase once age determination is complete for all the culled individuals. Such a high number is unsustainable in terms of future hunting management.

Culling each of these alphas has either caused the weakening or disbanding of a pack, leading to higher numbers of individuals or small groups of wolves roaming around unable to optimize their hunting. This is exactly the way to create more problem wolves that willingly come close to human habitation or begin killing hunting dogs. Additionally, several worrying cases have surfaced, where wolves have intentionally been driven towards habitation or have been deliberately wounded to gain more population control or damage control permits for hunting these “problem individuals”. The goal of the wolf management plan is to uphold a viable population in Finland, but at this current rate, the trial wolf cull also appears to have failed.

What next? The future of the wolf cull will be determined during the fall of 2016. The wolf is obviously a species that causes so many societal conflicts, errors in management, and people taking the law into their own hands, that we need to question whether the wolf should remain a species that can be hunted by the general public. Nevertheless, the wolf population does need both management and protection in the future. Perhaps Finland should consider a model where wolf hunting is carried out solely by the (game) authorities. The population control process could remain the same as before, which would allow the cull of problematic individuals and the regulation of pack sizes. But the professional skills of the proper authorities would ensure that overreactions and the killing of alpha individuals could be prevented, which in the long-term could help stabilize the whole population and mitigate wolf-human conflicts.

Beavers restore the dead wood of boreal forests

Dead wood is a necessary element for numerous species living in the boreal zone. It functions as a food resource, nesting space or growth substrate for several mammals, fungi, insects, and birds. Dead wood is produced through two main mechanisms: senescence and disturbances e.g. forest fires or wind damage. A controlled forest has less ageing trees and disturbances, and currently up to 90% of Fennoscandian forests have been influenced by forest management. The recent drop in dead wood levels due to intensive forest management across the globe has concurrently led to dead wood-dependent (= saproxylic) species becoming rare as well, which weakens food webs and ecosystem functionality. Managed forests may only contain a few cubic meters of dead wood per hectare, while dead wood levels in old-growth forests and forests influenced by disturbances can rise up to hundreds of cubic meters per hectare.

Beaver, the ecosystem engineer © Sari Holopainen

Beaver, the ecosystem engineer © Sari Holopainen

Strong disturbances are less frequent in moist lowland areas of the boreal zone, where dead wood is mainly created as single trees die due to competition and ageing. However, beavers act as wetland ecosystem engineers, raising floodwaters through the damming of water systems. These floodwaters kill surrounding shore forests due to oxygen deprivation, thus creating significant amounts of dead wood into the habitats. In certain cases the flooding may kill entire forest stands. Beavers can therefore be considered the main natural disturbance factor of lowland forests.

Beavers require wood for food and as a building material for their nests and dams. Foraging for woody materials causes the resource to run out within a few years, forcing the beavers to move location. The process of flooding and dead wood creation begins again in a new area, thus producing a continuation of dead wood hotspots into the landscape. Eventually after several years the beavers can return to a previously inhabited location, which will be then be repeatedly subjected to their engineering. These hotspots may be very important to dead wood -dependent species, especially as they uphold a network and continuous supply of different-aged dead wood.

Calculating dead wood levels at a beaver flood - spot the researchers! ©Mia Vehkaoja

Calculating dead wood levels at a beaver flood – spot the researchers! ©Mia Vehkaoja

Despite an overall decrease in dead wood levels, certain types of dead wood have become rarer in the boreal forest than others. Currently the rarest forms are standing dead trees (snags) and deciduous dead wood. Both have declined more rapidly than other types due to forest management actions and attitudes. Beavers create a broad range of dead wood types (e.g. downed wood, stumps and coniferous dead wood), but they particularly aid in the production of snags and deciduous dead wood. This is good news for many saproxylic species, as these organisms are often strongly specialized, utilizing very specific dead wood types.

The dead wood produced by beaver-induced flooding is also very moist, which may affect the wood-decay fungi species that begin colonizing the dead wood. For example, sac fungi are more tolerant of wet conditions, and may therefore outcompete Basidiomycetes at beaver sites. This in turn will lead to differing invertebrate communities that utilize sac fungi instead of Basidiomycetes. Very different dead wood –dependent species assemblages may therefore be formed at beaver sites compared to fire areas of clear-cuts. The interactions of these species are currently poorly understood.

The beaver offers a possibility for all-inclusive ecosystem conservation compared to the conservation of single species. The species could be used to produce dead wood and restore the shore forests of wetlands.

Our research group has recently published an article concerning the impacts beavers have on boreal dead wood. The article can be accessed from http://www.sciencedirect.com/science/article/pii/S0378112715005757

Calculating dead wood levels at a beaver flood - spot the researchers! ©Mia Vehkaoja

Calculating dead wood levels at a beaver flood – spot the researchers! ©Mia Vehkaoja

The Red List of Ecosystems: assessing the extinction risk of ecosystems

Alps and Krim waterfall ©Mia Vehkaoja

Alps and Krim waterfall ©Mia Vehkaoja

Most people are familiar with the concept of extinction, and are aware of the IUCN Red List of Threatened Species (RLTS), a classification of the Earth’s organisms into different categories based on their population levels and dangers facing their survival. RLTS was founded in 1964, and was initially considered the best way forward in global conservation. Unfortunately, the plan of documenting all living organisms of the planet has proven cumbersome and slow, and currently the project’s aim is to classify 160 000 species by 2020. That accumulates to only 8% of all species currently known to exist. The task seems daunting and never-ending. Although certain individual species have been brought back from the brink of extinction thanks to having their “specs” measured, the RLTS has been unable to curb or stop the increasing population decline of countless species.

As a list of individual species has proved inadequate to counter biodiversity loss, the next step forward was taken during the 2000s with the formation of the Red List of Ecosystems (RLE). The idea behind this is fairly simple; each ecosystem is compared to a set of criteria, assessed in terms of its risk of collapsing (meaning the disintegration of its functioning leading to collapses in biodiversity), and finally categorized according to its current functioning and stability. It is in fact a hazard assessment for the extinction risk of individual ecosystems. The criteria used in evaluating each ecosystem includes assessing how much of their original flora and fauna have been converted, degraded or destroyed, and how much of their original size remains.

Classification is pretty similar to that of the RLTS: ecosystems can currently be at no risk of collapse (least concern), at three different levels of being threatened (vulnerable, endangered, or critically endangered), or they may already be approaching a final state of degradation (collapse). We may also have too little information (data deficient) to make an assessment, or their health may not have been appraised yet (not evaluated).

Once classified, appropriate planning and management measures can be taken to enhance or restore ecosystem functionality, which often also improves the stability of societies living within the influence of these ecosystems. For example, wetland restoration benefits societies by providing cleaner water for household use and by preventing or lessening flood and drought damage.

The RLE is an important tool for communicating between ecologists, decision-makers, and developers. The system provides robust and straightforward guidelines that are applicable to all types of ecosystems around the globe. One noteworthy goal of the IUCN is to assess and showcase ecosystems that are currently doing well, not just those that are at risk of collapse. Such well-to-do ecosystems are important, so as to pinpoint the reasons and most efficient management practices that have led to their current health.

Desert in Dubai ©Mia Vehkaoja

Desert in Dubai ©Mia Vehkaoja

However, improvement is always necessary. One such avenue for improvement lies in getting nations to collaborate together in conserving ecosystems crossing borders. This would greatly improve the connectivity of landscapes, improving habitats for migratory species, species with large habitat area requirements etc. But when used jointly with other conservation measures, such as the assessment of ecosystem services, spatial management planning, and the IUCN RLTS, this new method seems very promising. Currently the aim of the IUCN is to have all the Earth’s ecosystems assessed by 2025. This will be carried out at the national and regional level, and results will be freely accessible in an online database.

For more info and case studies, go to http://www.iucnredlistofecosystems.org/about-us/red-list-ecosystems/

For a practical assessment guide, visit http://www.iucnredlistofecosystems.org/wp-content/uploads/2015/04/Rodriguez-etal-2015-A-practical-guide-IUCN-RLE_erratum.pdf

The 4th Pan European Duck Symposium in Hanko

The 4th Pan European Duck Symposium was organized in Hanko, the southernmost city in Finland 7.–11.4.2015. The symposium covered subjects widely from duck population dynamics to habitat changes, hunting and management. The following is a short report of a few presentations from the first two days.

Mikael Kilpi and Aleksi Lehikoinen giving the opening words in PEDS4

Mikael Kilpi and Aleksi Lehikoinen giving the opening words in PEDS4

Game husbandry manager Jarkko Nurmi from the Finnish Wildlife Agency used his opening words to underline the need for flyway management in duck populations. As he showed, different scales for successful management of the game species exist; e.g. forest grouse can be managed very locally, while ducks need cooperation between countries located on their flyway. Finland is responsible for offering breeding habitats for ducks. A few years ago the Finnish Wildlife Agency set up a project called “The return of rural wetlands”, which was presented by special planner Mikko Alhainen. 44 model wetlands have been established during this EU-funded project, in addition to several others inspired by these models. The wetland construction has been cost-efficient with minimal bureaucracy, and has encouraged landowners to restore their wetlands or establish new ones. The project has been a success in every way and ducks have accepted the man-made wetlands very rapidly.

Associate Professor at Utah State University David Koons, the plenary speaker of the first day

Associate Professor at Utah State University David Koons, the plenary speaker of the first day

Associate Professor at Utah State University David Koons, the plenary speaker of the first day, introduced next-generation methods for studying waterfowl population dynamics. By combining bird and location data it may be possible to move smoothly from site-level studies to the flyway and continental levels. Also combining several types of population data it may be possible to reduce analyses bias. As a case study, he showed that splitting scaup data into yearly processes explained by population parameters allows researchers to comprehend that the cause behind population declines is in the disappearing recovery years, while individual parameters haven’t changed as much.

The plenary speaker of the second day, Adjunct Professor in Biology at the University of Saskatchewan Rober Clark.

The plenary speaker of the second day, Adjunct Professor in Biology at the University of Saskatchewan Rober Clark.

The plenary speaker of the second day, Adjunct Professor in Biology at the University of Saskatchewan Rober Clark, presented the effects of climate change on duck populations. Snow cover in Canada has decreased more than expected by prediction models. Dry seasons will become more common and severe, thus affecting the availability of wetlands, the food webs therein and various competitive interactions. Clark also underlined that wetland dynamics will change in boreal areas due to land use. It seems that late-nesting duck species such as scaups and scoters are most vulnerable to climate change, while early breeders such as common goldeneyes are more tolerant. These patterns are pronounced both in Europe and North America.

Michael Johnson gave an introduction to duck management in North America, especially in the U.S. prairie pothole region. Large changes have occurred, of which some have even accidentally supported duck populations. The increase of grassland cover, wet years and changes in predator communities have raised duck populations to remarkably high levels. However, the grassland area has been disappearing rapidly, which will be reflected in duck populations according to Johnson. He underlined that much of the grasslands and wetlands are unprotected. The numbers of hunters are declining, and thus conservation funding might be difficult to find.

Michel Gendron gave an overview of duck hunting in Canada, where hunter numbers have also decreased. The duck harvest in Canada has recently stabilized after a drop from the 1970s to 2005. Goose hunting has concurrently steadily increased due to the growth of goose populations and liberalization of hunting regulations. The annual National Harvest Surveys in Canada are conducted by 1) questionnaires to find out the hunting activity and harvest of species, and 2) with wing and tail collection to generate information on the age- and sex ratios of the species hunted.

In Russia, the yearly hunting quarry is studied by identifying species and sexes from photographs hunters are asked to send to researchers, as presented by Alexander Solokha. All the species are studied during the autumn hunt, while the mallard bag is also observed during the spring hunt.

The North Atlantic Oscillation (NAO) was addressed in several presentations as an explanation for duck population dynamics. Aleksi Lehikoinen presented the effects of winter and summer NAO on the variation of duck population dynamics in 14 waterbird species. Jukka Rintala showed that the NAO explained a total of 20% of the environmental variance in a group of 11 duck species. The umbrella species, varying with other species, were the garganey and common pochard. Sari Holopainen found that the brood production of the common teal in Finland is varying with the winter NAO index and exceptionally good brood production demands two highly positive NAO winters. The mechanism behind this is believed to be that during high winter NAO index years Finland receives more snow and thus more seasonal ponds are available for the ducks during the breeding season. Wintering numbers of the species were more stochastic, but some carry-over effects can be found. Anthony Fox suggested that wigeon reproduction to also be influenced by the NAO index, but the summer one in this case. Density-dependent processes were additionally found from the wigeon reproduction numbers.

Climate change has affected the migration phenology of common teals in France since the 1950s, as presented by Matthieu Guillemain. Birds arrive earlier and their movements during the winter have been diluted. In addition, the body condition of the wintering ducks has improved. Teals that have once wintered in Camargue seem to be returning the next year. However, as underlined by Guillemain, the hunting mortality in Camargue is high. As the duck turn-over rate is high, the stability of the wintering population is uncertain.

Several duck species have declined in Finland. Especially pronounced is the decline of species living in eutrophic lakes. It might be that vegetation overgrowth is causing the problem. Kim Jaatinen presented the cost efficient analysis of different management actions when working with overgrown wetlands. According to his analyses, cattle grazing is the best tool concerning bird diversity, and because it is also cheap, it was shown to be the most cost-efficient. Cutting and harrowing were also good alternatives, but because they do not produce dung, they are not as beneficial to some bird species as cattle grazing. Dredging was found to be the most expensive tool to control overgrowth. Ilkka Sammalkorpi presented that biomanipulation by removing fish could also be done in wetlands important for ducks.

Grazing by cattle maintains open shore meadows benefiting efficiently waterbird breeding. © Veli-Matti Väänänen

Grazing by cattle maintains open shore meadows benefiting efficiently waterbird breeding. © Veli-Matti Väänänen

In addition to freshwater ducks, some sea ducks have also been declining in Finland. Lasse Kurvinen showed dramatic trends of several common eider populations from the Finnish archipelago. Especially large colonies have disappeared. It seems that the colony-specific dynamics are mainly predation driven.

Opposite to Europe, Sidi Imad Cherkaoui told that the wintering numbers and distribution of several species in Morocco have increased during last decade. This is despite wetlands in the country meeting severe problems, such as drainage and urbanization. The ruddy shelduck is one of the species increasing its numbers in Morocco, and also in Netherlands as presented by Sjoerd Dirksen. His studies showed that the moulting populations of the species might be higher in some Central European countries than previously though.

Ducks offer ecosystem services, for instance by supporting connectivity for plants and invertebrates in isolated wetlands. The subject is now much studied, but was presented by Erik Kleyheeg in the symposium. Seeds carried on the bodies of ducks can end up far away from their origin, even hundreds of kilometers during the migration.

The Hanko bird observatory bird station produces a lot of information about migrating ducks. Just 70 kilometers south of the Hanko bird observatory station lays the Estonian bird observatory station Põõsaspea. Margus Ellermaa showed that even with this short distance between the observatories it is enough to create a huge difference between the numbers of migratory ducks due to differing migration paths.

PEDS4 had two options for the field trip. Here the participats are at the Bengtskär lighthouse photographing migrating  goldcrests.

PEDS4 had two options for the field trip. Here the participats are at the Bengtskär lighthouse photographing migrating goldcrests.

Mallard farming is a big business in Europe and every year 3 million farmed mallards are released into the wild. Considering that the population estimate for mallards in Europe is 7,5 million, the farmed ones compose a huge proportion. Most of the farmed individuals are hunted, and as shown by Jocelyn Champagnon, their survival during the first half a year is low, about half of the wild ones. Still, genetic mixing to the wild population has happened, as presented by Gunnar Gunnarsson. Present day mallards in Europe have wider, shorter and higher bills than the species had prior to large-scale farming. Mallards also show to have “alien genes”: their occurrence is especially pronounced in mallards in the core farming areas in Western Europe, while the trait is rarer in mallards of the remote areas without farming.

Taej Mundkur from Wetlands International presented a study concerning critical habitats for waterbirds in the Arctic region. Based on species-specific habitat requirements the study aims to find the critical habitats of different stages of the species’ life cycles. The long-tailed duck and Steller’s Eider have been used as pilot species. The project should help find new conservation areas and critical areas that are currently under threat.

Read more: Wetland Ecology Group web pages and our blog in Finnish

#PEDS4

Triage — cost-effective or emotionally empty conservation

The concept of triage comes from battlefields and trauma rooms. The idea is that patients are divided into three categories: patients with minor problems (not needing immediate actions), patients with a high probability of dying no matter what actions are carried out, and patients that can be saved by urgent and correct procedures. The concept has been expanded to conservation, but in ecology triage refers to the conservation prioritisation of species. The ones to be saved provide unique or important functions to ecosystems, and the ones to be let go either don’t have such special ecosystem roles or, on the other hand are facing almost certain extinction, which means that their viable population size is well below minimum.

Triage can also be seen as cost-effective conservation. It is a way to efficiently allocate conservation resources, both financial and labour. We should not focus our limited resources on species that are doomed or expensive to save or on the other hand do not need our aid to last out in the future. On the contrary, we should emphasise the conservation of species that are more likely to survive with the right kind of conservation actions.

Triage is very controversial and can be seen as emotionally empty. It has gained a lot of counterarguments that challenge how we can allow extinctions and how we can know that triage is not leading to an extinction cascade. The fundamental concept of conservation biology is to prevent extinctions, not allow. Opponents of ecological triage state that all species have an inherent value, and therefore should be protected. They also highlight that triage is giving governments the opportunity to reduce their funding for conservation, and by because of this conservationists are forced to assign more species and ecosystems to extinction. According to them the aim should not be cost-effectiveness but finding new funding opportunities for conservation.

In an ideal world it could be plausible to aim for zero extinction, but in the real world this is impossible. Extinctions are, of course, a normal part of life, at least over geological scales. However, the current global extinction rate of species is at the same level as when dinosaurs lived. So we are heading for the sixth mass extinction. The ever-expanding human population has exploited and will continue exploiting the Earth’s resources in a way that necessitates some difficult decisions.

Australia is a ´good example´ of things gone bad. It has the highest current extinction rate of mammals, and has lost nearly 40% of its forest cover since European colonisation. Despite the fact that Australia has used millions on conservation, the country has been unable to take a single species off the national endangered list during the last decade. Kakadu National Park and Great Barrier Reef are the two biggest, most well-known and best-funded protected areas in Australia, and still their biodiversity is declining. Now the Australian government has woken up and taken measures against the rapid species decline. Australia is leading the way to triage-based conservation.

The giant panda (Ailuropoda melanoleuca) can be considered an example of a doomed species. The population size of the panda has been very low for decades and a considerable amount of the individuals live in captivity. Conservation has placed millions of dollars every year into saving the species and aiding its reproduction. Zoos all over the world pay millions every a year to have a panda in their zoo. No other species costs this much, and even the head of the National Zoo of Washington claims that ´Nobody would ever commit this kind of money to any other species´. Panda conservation is not cost-effective so in triage-based conservation the panda is doomed and should be left without conservation aid. On the other hand, the panda is an iconic species for the WWF and provides a lot of attention to nature conservation. With the help of the panda WWF can collect contributions to other species as well. But triage supporters challenge the idea and claim that pandas are just poster animals for the zoo industry. Whatever the truth, maybe the money put into reproducing pandas in zoos could be allocated to preserve the habitats of pandas. However, it has been questioned whether their habitat in the wild is large enough to sustain them. Maybe we should just let them go and focus on other species and habitats.

The Giant Panda in Berlin Zoo. Caring for one giant panda costs millions of dollars in a year. © Mia Vehkaoja

The Giant Panda in Berlin Zoo. Caring for one giant panda costs millions of dollars in a year. © Mia Vehkaoja

Triage is also controversial in my own head. My first reaction to triage was that we should unconditionally protect all species and ecosystems, and permit their survival. On the other hand, I know we don’t have enough resources to save them all, so we need to have some kind of system on how to evaluate the species and habitats that should be saved. Triage could be one good alternative, but instead of using triage on species, we should use it on ecosystems. And furthermore we should focus on finding the ecosystem engineer species, because by conserving them we could conserve entire ecosystems. The ecosystem engineers can be seen as species contributing the most to ecosystem function, and from the triage point of view they are therefore earmarked for conservation. Nature is a complex ensemble of different interdependent components, so we should treat it according to its features.