Page not found – Conservation Jobs https://www.conservationjobs.co.uk Careers, Courses, Events and More Tue, 26 Mar 2024 17:21:26 +0000 en-GB hourly 1 https://wordpress.org/?v=4.9.25 Sawfish Facing Extinction https://www.conservationjobs.co.uk/articles/sawfish-facing-extinction/ https://www.conservationjobs.co.uk/articles/sawfish-facing-extinction/#comments Sat, 10 Jul 2021 09:43:00 +0000 https://www.conservationjobs.co.uk/?p=77924 Sawfish have disappeared from half of the world’s coastal waters and the distinctive shark-like rays face complete extinction due to overfishing, according to a new study that has been published in the journal Science Advances.

Sawfish, named after their unique long, narrow noses lined by teeth, called rostra, that resemble a sawblade, were once found along the coastlines of 90 countries but they are now among the world’s most threatened family of marine fishes, presumed extinct from 46 of those nations. There are 18 countries where at least one species of sawfish is missing, and 28 more where two species have disappeared.

According to the researchers Helen Yan and Nick Dulvy from Simon Fraser University, three of the five species of sawfish are critically endangered, according to the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, and the other two are endangered.

Their teeth on their rostra are easily caught in fishing nets. Sawfish fins are among the most valuable in the global shark fin trade and rostra are also sold for novelty, medicine and as spurs for cockfighting. Habitat destruction is also a serious threat. Coastal and estuarine habitats, including mangrove and seagrass meadows, are often degraded by human developments and pollution, and these are important habitats for sawfish, especially their young.

The current presence of all sawfishes world-wide is unknown, but Dulvy warns complete extinction is possible if nothing is done to curb overfishing and to protect threatened habitats, such as mangroves, where sawfish can thrive. He says: “Through the plight of sawfish, we are documenting the first cases of a wide-ranging marine fish being driven to local extinction by overfishing. We’ve known for a while that the dramatic expansion of fishing is the primary threat to ocean biodiversity, but robust population assessment is difficult for low priority fishes whose catches have been poorly monitored over time. With this study, we tackle a fundamental challenge for tracking biodiversity change: discerning severe population declines from local extinction.”

The study recommends that international conservation efforts focus on eight countries (Cuba, Tanzania, Columbia, Madagascar, Panama, Brazil, Mexico and Sri Lanka) where conservation efforts and adequate fishing protections could save the species. It also found Australia and the United States, where adequate protections already exist and some sawfish are still present, should be considered as “lifeboat” nations.

“While the situation is dire, we hope to offset the bad news by highlighting our informed identification of these priority nations with hope for saving sawfish in their waters. We also underscore our finding that it’s actually still possible to restore sawfish to more than 70 per cent of their historical range, if we act now,” said Yan.

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Rare Australian Bee Discovery https://www.conservationjobs.co.uk/articles/rare-australian-bee-discovery/ https://www.conservationjobs.co.uk/articles/rare-australian-bee-discovery/#respond Fri, 09 Jul 2021 12:04:29 +0000 https://www.conservationjobs.co.uk/?p=78001 A widespread field search for a rare Australian native bee not recorded for almost a century has found it’s been there all along, but like so many rare species, is probably under increasing pressure to survive.

Only six individuals were ever found, with the last published record of this Australian endemic bee species, Pharohylaeus lactiferus (Colletidae: Hylaeinae), from 1923 in Queensland.

“This is concerning because it is the only Australian species in the Pharohylaeus genus and nothing was known of its biology,” Flinders University researcher James Dorey says in a new scientific paper in the Journal of Hymenoptera Research.

The hunt began after fellow bee experts Olivia Davies and Dr Tobias Smith raised the possibility of the species’ extinction based on the lack of any recent sightings. The ‘rediscovery’ followed extensive sampling of 225 general and 20 targeted sampling sites across New South Wales and Queensland.

Along with extra bee and vegetation recordings from the Atlas of Living Australia, which lists 500 bee species in NSW and 657 in Queensland, the Flinders researchers sought to assess the latest levels of true diversity warning that habitat loss and fragmentation of Australia’s rainforests, along with wildfires and climate change, are likely to put extinction pressure on this and other invertebrate species.

“Three populations of P. lactiferous were found by sampling bees visiting their favoured plant species along much of the Australian east coast, suggesting population isolation,” says Flinders University biological sciences PhD candidate James Dorey.

Highly fragmented habitat and potential host specialisation might explain the rarity of P. lactiferus. Australia has already cleared more than 40% of its forests and woodlands since European colonisation, leaving much of the remainder fragmented and degraded.

Mr Dorey says: “My geographical analyses used to explore habitat destruction in the Wet Tropics and Central Mackay Coast bioregions indicate susceptibility of Queensland rainforests and P. lactiferus populations to bushfires, particularly in the context of a fragmented landscape.”

The study also warns the species is even more vulnerable as they appear to favour specific floral specimens and were only found near tropical or sub-tropical rainforest – a single vegetation type: “Collections indicate possible floral and habitat specialisation with specimens only visiting firewheel trees and Illawarra flame trees to the exclusion of other available floral resources.”

Known populations of P. lactiferus remain rare and susceptible to habitat destruction (e.g. from changed land use or events such as fires). Mr Dorey explains: “Future research should aim to increase our understanding of the biology, ecology and population genetics of P. lactiferous. If we are to understand and protect these wonderful Australian species, we really need to increase biomonitoring and conservation efforts, along with funding for the museum curation and digitisation of their collections and other initiatives.”

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Counting Elephants…From Space https://www.conservationjobs.co.uk/articles/counting-elephants-from-space/ Thu, 08 Jul 2021 13:47:38 +0000 https://www.conservationjobs.co.uk/?p=77856 For the first time, scientists have successfully used satellite cameras coupled with deep learning to count animals in complex geographical landscapes, taking conservationists an important step forward in monitoring populations of endangered species.

For this research, the satellite Worldview 3 used high-resolution imagery to capture African elephants moving through forests and grasslands. The automated system detected animals with the same accuracy as humans are able to achieve. The results were published Remote Sensing in Ecology and Conservation.

The algorithm that enabled the detection process was created by Dr Olga Isupova, a computer scientist at the University of Bath. The project was a collaboration with the University of Oxford and the University of Twente in the Netherlands.

Dr Isupova said the new surveying technique allows vast areas of land to be scanned in a matter of minutes, offering a much-needed alternative to human observers counting individual animals from low-flying airplanes. As it sweeps across the land, a satellite can collect over 5,000 km² of imagery every few minutes, eliminating the risk of double counting. Where necessary (for instance, when there is cloud coverage), the process can be repeated the next day, on the satellite’s next revolution of Earth.

The population of African elephants has nose-dived over the past century, mainly due to poaching and habitat fragmentation. With only 40,000-50,000 elephants left in the wild, the species is classified as endangered.

Dr Isupova said: “Accurate monitoring is essential if we’re to save the species. We need to know where the animals are and how many there are.”

Satellite monitoring eliminates the risk of disturbing animals during data collection and ensures humans are not hurt in the counting process. It also makes it simpler to count animals moving from country to country, as satellites can orbit the planet without regard for border controls or conflict.

This study was not the first to use satellite imagery and algorithms to monitor species, but it was the first to reliably monitor animals moving through a heterogeneous landscape – a backdrop that includes areas of open grassland, woodland and partial coverage.

“This type of work has been done before with whales, but of course the ocean is all blue, so counting is a lot less challenging. As you can imagine, a heterogeneous landscape makes it much hard to identify animals,” added Dr Isupova.

The researchers believe their work demonstrates the potential of technology to support conservationists in their plight to protect biodiversity and to slow the progress of the sixth mass extinction, the ongoing extinction event triggered by human activity.

“We need to find new state-of-the-art systems to help researchers gather the data they need to save species under threat,” says Dr Isupova.

African elephants were chosen for this study for good reason – they are the largest land animal and therefore the easiest to spot. However, Dr Isupova is hopeful that it will soon be possible to detect far smaller species from space: “Satellite imagery resolution increases every couple of years, and with every increase we will be able to see smaller things in greater detail. Other researchers have managed to detect black albatross nests against snow. No doubt the contrast of black and white made it easier, but that doesn’t change the fact that an albatross nest is one-eleventh the size of an elephant.”

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Canada Lynx Losing Ground https://www.conservationjobs.co.uk/articles/canada-lynx-losing-ground/ Wed, 07 Jul 2021 16:21:28 +0000 https://www.conservationjobs.co.uk/?p=77439 A massive monitoring study led by Washington State University researchers has found lynx on only about 20% of its potential habitat in the state. The study, published in the Journal of Wildlife Management, covered more than 4,300 square miles (7,300 km) in northeastern Washington with camera traps but detected lynx in only 29 out of 175 monitored areas.

The results paint an alarming picture not only for the persistence of lynx but many other cold-adapted species, said Dan Thornton, an assistant professor in WSU’s School of the Environment: “Lynx are good sentinel species for climate change. They are specialised, have larger ranges and need really cold, snowy environments. So, as they go, they are like an early warning system for what’s going to happen to other climate sensitive species.”

Wildfire, rising temperatures and decreasing snowpack have all hurt the lynx’s ability to survive in Washington, the researchers found. In the last 24 years, large wildfires have ripped through northeastern parts of the state, destroying habitat for lynx and their favourite food: snowshoe hare. It can take as long as 20 to 40 years for that landscape to recover.

The lack of snow and cold are also a problem, as lynx with their bigger paws are specially adapted to hunt on snow and for the prey that live there. As temperature rises, warmer adapted species like bobcat and cougar could also bring competition into lynx territory.

“We learned that lynx are responding strongly to many of these factors – snow conditions, temperature and fire – that are likely to change even more as the climate warms,” said Thornton.

The connection to Canadian populations is also key for the lynx survival in Washington, and that connection is complicated by differing conservation status. In Washington state, they are protected at the state and federal levels as a threatened species. In Canada, they are harvested for their pelts. The lynx’s protected status in the U.S. may also change. Lynx are currently found in Maine, Minnesota, Montana, Colorado, Idaho and Washington, but a 2016 federal draft assessment found the species would disappear from its northern range without protection by 2100. However, a new assessment in 2018 concluded that the lynx could be removed from threatened status under the federal Endangered Species Act.

Living in high, remote areas, lynx are challenging to study, and estimates of actual individuals are difficult to make, but according to an analysis by the Washington State Department of Fish and Wildlife based on data collected in the 1980s, the state used to have about 7,800 square miles of habitat capable of supporting 238 animals. In 2017, that estimate was revised down to about 2,300 square miles capable of supporting 38 to 61 lynx. This latest study adds strong evidence that their territory in Washington is further contracting.

To document the elusive animals, lead author Travis King covered thousands of kilometres and spent two summers in the field. He also relied upon many partners and volunteers, ranging from government natural resource agency employees and conservation groups to hikers and citizen scientists. The researchers and volunteers deployed and collected 650 camera traps which generated more than 2 million images which were, in turn, sorted with the help of dozens of WSU student volunteers. This is the first time such a comprehensive method using camera traps to track lynx has been employed. Thornton and his colleagues are now working to use the method to estimate the lynx range in Glacier National Park in Montana.

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Birds Helping Birds https://www.conservationjobs.co.uk/articles/birds-helping-birds/ Tue, 06 Jul 2021 11:47:03 +0000 https://www.conservationjobs.co.uk/?p=77925 Birds are the most diverse group housed by zoos around the world, but zoo-based research tends not to focus on birds. A new article published in the journal Birds, by Dr Paul Rose of the University of Exeter, suggests zoos can improve management of birds by looking at how species live in their natural habitats.

Likewise, birds living under the care of humans can also help guide and develop conservation action for those living in the wild. Dr Rose explains: “Research into wild birds is extremely useful for furthering how birds are managed in zoos. For species of conservation concern, zoo professionals can be linked with field biologists to share information on how to best care for these species in captivity and how to develop and formulate conservation actions. We can use proxy species – those common in zoos – to develop practices for conservation that can be used for less familiar species that might be of concern and need help from information gathered through things such as captive breeding. Or we can promote the threats that these not-in-the-zoo species face by using the commoner species as an ambassador. We do this through my work at the Wildfowl & Wetlands Trust, promoting the rarer species of flamingo that are in the wild using the commoner ones we keep in the living collection.”

In the review, Dr Rose uses hornbills as an example, a species of bird that is essential to the long viability and sustainability of biodiversity in the rainforest. The helmeted hornbill, a critically endangered species, plays an important role in the dispersal of seeds within pristine, undistributed areas of south-east Asian rainforests.

The population decline of the helmeted hornbill has been caused by poaching of the birds for their “ivory,” the large casque on the bird’s head and bill that can be up to 10% of its overall body mass. Whilst the helmeted hornbill is not found in captivity, other species of large hornbill are. By looking at the ecological role of the helmeted hornbill in its natural habitat, zoos have been able to design enclosures that will increase chances of reproduction.

For example, by identifying the temperature and humidity range of hornbill nesting sites in the wild which are more likely to hatch eggs, zoos have been able to use this data to enable them to match these environmental conditions as closely as possible. A similar situation happened with the Guam kingfishers, a species that is extinct in the wild and reliant on captive breeding for its survival.

Data from the nesting locations of the closely related Pohnpei Kingfisher, found on a neighbouring island, showed that temperatures were hotter than those sometimes provided for captive Guam kingfishers. The findings led to zoos raising the temperature to improve nesting success amongst the species.

Zoos have also been able to guide conservation action for hornbills living in the wild by monitoring the behaviour of these birds and discovering that using nest boxes enhances the quality of habitats for hornbills to breed in, which has led to these boxes being built in areas of the helmeted hornbill’s range in Borneo.

“The effect of visitors on zoos can also help direct future research questions and increase understanding of birds under human care,” adds Dr Rose. “Developing zoo bird exhibits to theme them around specific conservation messages can be used to promote wider understanding of the threats faced by wild birds specifically and hopefully encourage human behaviour change that benefits ecosystem health.”

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Fish Stock Modelling Inspired by Social Media https://www.conservationjobs.co.uk/articles/fish-stock-modelling-inspired-by-social-media/ https://www.conservationjobs.co.uk/articles/fish-stock-modelling-inspired-by-social-media/#respond Mon, 05 Jul 2021 06:33:17 +0000 https://www.conservationjobs.co.uk/?p=77570 University of Queensland School of Veterinary Science researcher Dr Nicholas Clark and colleagues from the University of Otago and James Cook University have assembled a holistic picture of climate change’s impacts on fish stocks in the Mediterranean Sea, using innovative techniques. Traditional mathematical models have had a boost by new technology.

They describe their research in their own words. Lead author Dr Clark said: “Usually, when modelling ecosystems to understand how nature is changing, we build models that only focus on the effects of the environment. But it’s just not accurate enough. Newer models – commonly used in social media to document people’s social interactions – offer an exciting way to address this gap in scientific knowledge. These innovative network models give us a more accurate picture of reality by incorporating biology, allowing us to ask how one species responds to both environmental change and to the presence of other species, including humans.”

The team used this technique to analyse fish populations in the Mediterranean Sea, a fisheries-based biodiversity hotspot with its future under threat from rapidly warming seas. Their results are published in Nature Climate Change.

Dr Clark continues: “Experts from fisheries, ecology and the geographical sciences have compiled decades of research to describe the geographical ranges for more than 600 Mediterranean fish species. We put this information, along with data from the Intergovernmental Panel on Climate Change’s sophisticated climate models into our network model. We found that warming seas, particularly in winter, have widespread effects on fish biodiversity.”

The University of Otago’s Associate Professor Ceridwen Fraser said winter warming was often overlooked when people thought about the impacts of climate change: “A great deal of research and media attention has been on the impacts of extreme summer temperatures on people and nature, but winters are getting warmer too. Interestingly, coastal water temperatures are expected to increase at a faster rate in winter than in summer. Even though winter warming might not reach the extreme high temperatures of summer heatwaves, this research shows that warmer winters could also lead to ecosystem disruption, in some cases more than hotter summer warming will. Our results suggest that winter warming will cause fish species to hang out together in different ways, and some species will disappear from some areas entirely.”

The researchers hope the study will emphasise the need to understand and address climate change.

“If fish communities are more strongly regulated by winter temperatures as our model suggests, this means that fish diversity may change more quickly than we previously thought. Catches for many bottom-dwelling and open-ocean fishery species in the Mediterranean Sea have been steadily declining, so any changes to fish communities may have widespread economic impacts. For the sake of marine ecosystems and the people whose livelihoods depend on them, we need to gain a better understanding of how ocean warming will influence both species and economies,” explained Dr Clark.

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Biotelemetry Reveals Behaviour of Rare Eagle Ray https://www.conservationjobs.co.uk/articles/biotelemetry-reveals-behaviour-of-rare-eagle-ray/ https://www.conservationjobs.co.uk/articles/biotelemetry-reveals-behaviour-of-rare-eagle-ray/#respond Sun, 04 Jul 2021 11:26:49 +0000 https://www.conservationjobs.co.uk/?p=77561 The whitespotted eagle ray, found in estuaries and lagoons throughout Florida, is listed as “near threatened” on the International Union for Conservation of Nature’s “Red List of Threatened Species.” Keeping tabs on this highly mobile species for conservation efforts can be extremely challenging, especially for extended periods of time.

Researchers from Florida Atlantic University’s Harbor Branch Oceanographic Institute used uniquely coded transmitters and acoustic telemetry to give them a leading edge to unravel fine-scale movement, behaviour, and habitat use of whitespotted eagle rays in Florida’s Indian River Lagoon. Biotelemetry provided the researchers with unique insights into this species’ occupancy, which is not apparent at the landscape-scale.

Despite being a state-protected species in Florida for more than two decades, this study is the first to characterise the ecology and fine-scale habitat use of whitespotted rays in Florida while also identifying areas of potential interactions between this species and multiple environmental threats. For the study, researchers followed seven mature individuals (six males and one female) and individually tracked them for a total of 119.6 hours. They used a tracking vessel to continuously and manually track the rays between June 2017 and August 2018.

Results of the study, published in the journal Endangered Species Research, show that rays use the deeper portions of the Indian River Lagoon, along Florida’s southeast coast, during the day and shallower portions during the night. In addition, they move faster while in the ocean and lagoonal habitats and slower in channels and inlets. This suggests that whitespotted eagle rays may spend more time foraging at night in the shallow water of the lagoon than during the daytime. These prolonged observations revealed affinities for habitats of considerable recreational and commercial importance, such as inlets, channels, and clam aquaculture lease sites close to shore.

Lead author Breanna DeGroot says: “Understanding channel use is crucial to evaluating risks and potentially developing strategies to mitigate negative impacts to the whitespotted eagle ray, as both channel and inlet habitats have high levels of human activity such as boating and fishing and are prone to coastal development impacts from dredging. In addition, these high traffic areas experience increased noise and chemical pollution.”

Rays also spent a larger proportion of time in the channels and inlet during the lighter and warmer portions of the day and used shallower depths during the cooler and darker portions of the day. Rate of movement significantly increased with temperature, suggesting that rays are more active during warmer periods. While previous studies have found that whitespotted eagle rays are influenced by tidal cycles, this study did not find any tidal patterns in ray habitat use or distribution.

Because more clammers work on lease sites during the day, interactions between the rays and growout sites may therefore be underestimated. Findings from this study will help to inform statewide conservation plans for the species and provide critical information to hard clam aquaculture farmers and restoration managers for the successful production of bivalves in the area.

“As coastal populations and development increase, there is more potential for whitespotted eagle rays to interact with human activities. In addition, intense coastal development such as dredging, construction, and pollution have been linked to habitat alteration, which may change the abundance and distribution of this species as has been documented with shark species in degraded habitats,” said so-author Matt Ajemian

As whitespotted eagle rays already display an affinity for these modified habitats, increased interactions with humans and added pollution and/or disturbances could result in changes to the species’ movement patterns and health. Ultimately, such human-induced habitat alterations could reduce the overall productivity of estuarine areas and, with time, exacerbate pressures already facing populations of this group of rays.

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Drought Forces Aardvarks to Feed in the Daytime https://www.conservationjobs.co.uk/articles/drought-forces-aardvarks-to-feed-in-the-daytime/ https://www.conservationjobs.co.uk/articles/drought-forces-aardvarks-to-feed-in-the-daytime/#respond Fri, 02 Jul 2021 10:54:43 +0000 https://www.conservationjobs.co.uk/?p=77539 Aardvarks occur across most of sub-Saharan Africa, but very few people have seen one, because they are solitary, mostly active at night, and live in burrows. They use their spade-like claws to build these burrows and to dig up ants and termites on which they feed. However, seeing aardvarks feeding in the day is becoming more common in the drier parts of southern Africa. While catching sight of an aardvark is a delight for many a wildlife enthusiast, researchers from the Wildlife Conservation Physiology laboratory at the University of the Witwatersrand warn that seeing aardvarks in the daytime does not bode well for this secretive animal.

The new research, published in Frontiers in Physiology, reveals what a shift from night-time to daytime activity means for the well-being of aardvarks in a warming and drying world. The researchers studied aardvarks living at Tswalu, a reserve in the Kalahari that lies at the edge of the aardvark’s distribution and provides support and infrastructure for researchers through the Tswalu Foundation.

Using biologgers, the researchers recorded body temperature and activity of aardvarks for three years, during which Dr Nora Weyer followed the aardvarks as part of her PhD research.

Assisted by satellite imaging that showed her how droughts affected the vegetation, Weyer was able to connect changes in aardvark behaviour and body temperature to what was happening in the aardvarks’ environment.

Dr Weyer’s research confirmed earlier findings by the team that there are times when the aardvarks switched their feeding to the day, and showed, for the first time, that drought caused that switch. “We suspected that it was drought, but we needed a long-term, comprehensive data set to confirm that it really was drought causing this unusual behaviour,” says co-worker Dr Robyn Hetem.

The Kalahari is arid at the best of times, but drought killed the vegetation that fed the ants and termites. Most of the ants and termites disappeared, leaving the aardvarks starving. “It was heart-breaking to watch our aardvarks waste away as they starved,” Dr Weyer said.

By shifting their activity from the cold nights to the warm days during dry winter months, aardvarks can save some of the energy needed to keep their body temperatures up. But those energy savings were not enough to see the aardvarks through a particularly bad drought in which many aardvarks died.

Dr Weyer explains: “Aardvarks have coped with the Kalahari’s harsh environment in the past, but it is getting hotter and drier, and the current and future changes to our climate might be too much for the aardvarks to bear.”

“Because the Kalahari is such a unique and potentially vulnerable ecosystem, we need to better understand whether its animals can cope with the increasingly dry conditions,” says Professor Andrea Fuller, co-worker and project leader of the Kalahari Endangered Ecosystem Project.

Disappearance of aardvarks from the Kalahari would be devastating for many other animals in this ecosystem. The large burrows which aardvarks build provide important shelters for many other species that cannot dig their own burrows, earning the aardvark the title of ‘ecosystem engineer’.

“Unfortunately, the future looks grim for Kalahari aardvarks and the animals that use their burrows. Tackling climate change is key, but there is no quick fix,” says Dr Weyer.

What conservationists do know is that any solution will require a much better understanding of what capacities animals have to cope with drought. And that means many more long-term comprehensive studies of physiology and behaviour.

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Endangered Vaquita Still Genetically Healthy https://www.conservationjobs.co.uk/articles/endangered-vaquita-still-genetically-healthy/ https://www.conservationjobs.co.uk/articles/endangered-vaquita-still-genetically-healthy/#respond Thu, 01 Jul 2021 13:09:31 +0000 https://www.conservationjobs.co.uk/?p=77786 The critically endangered vaquita (literally “little cow”, a species of porpoise endemic to the northern end of the Gulf of California) has survived in low numbers in its native Gulf of California for hundreds of thousands of years, a new genetic analysis has found. The study found little sign of inbreeding or other risks often associated with small populations.

Gillnet fisheries have entangled and killed many vaquitas in recent years and scientists believe that fewer than 20 of the small porpoises survive today. The new analysis demonstrates that the species’ small numbers do not doom it to extinction, however. Vaquitas have long survived and even thrived without falling into an “extinction vortex,” the new study showed. That’s a scenario in which their limited genetic diversity makes it impossible to recover.

The study was published in Molecular Ecology Resources. It’s lead author, Phil Morin, research geneticist at NOAA Fisheries’ Southwest Fisheries Science Centre, said: “The species, even now, is probably perfectly capable of surviving. We can now see that genetic factors are not its downfall. There’s a very good chance it could recover fully if we can get the nets out of the water.”

An increasing number of species in addition to the vaquita have maintained small but stable populations for long periods without suffering from inbreeding depression. Other species include the narwhal, mountain gorilla, and native foxes in California’s Channel Islands. Long periods of small population sizes may have given them time to purge harmful mutations that might otherwise jeopardize the health of their populations.

“It’s appearing to be more common than we thought that species can do just fine at low numbers over long periods,” said Morin, who credited the vaquita findings to genetic experts around the world who contributed to the research.

The idea that vaquitas could sustain themselves in low numbers is not new. Some scientists suspected that more than 20 years ago. Now advanced genetic tools that have emerged with the rapidly increasing power of new computer technology helped them prove the point.

“They’ve survived like this for at least 250,000 years. Knowing that gives us a lot more confidence that, in the immediate future, genetic issues are the least of our concerns,” said Barbara Taylor, research scientist at the Southwest Fisheries Science Centre.

The new analysis examined living tissue from a vaquita captured as part of a last-ditch international 2017 effort to save the fast-disappearing species. The female vaquita tragically died, but its living cells revealed the most complete and high-quality genome sequence of any dolphin, porpoise, or whale to date, generated in collaboration with the Vertebrate Genomes Project. Only in recent years have advances in sequencing technologies and high-powered computers made such detailed reconstruction possible.

While the vaquita genome is not diverse, the animals are healthy. The most recent field effort in fall 2019 spotted about nine individuals, including three calves, within their core habitat. The robust calves suggest that inbreeding depression is not harming the health of these last vaquita.

“These examples and others indicate that, contrary to the paradigm of an ‘extinction vortex’ that may doom species with low diversity, some species have persisted with low genomic diversity and small population size,” scientists wrote in the new study.

The genetic data suggest that the vaquita’s isolated habitat in the far northern Gulf of California has sustained roughly 5,000 vaquitas for around 250,000 years. The advent of gillnetting for fish and shrimp only a few decades ago drove vaquitas towards extinction, as they are incidentally caught in the nets.

More recently, Illegal gillnetting for totoaba, a fish about the same size and found in the same habitat as the vaquita, has compounded the losses. Totoaba were overfished by the mid-1970s and were listed as endangered by Mexico in 1975, and by the US in 1979. Today, international trade in totoaba is banned under CITES, a global agreement among governments to regulate or ban international trade in species under threat, but high demand from China for its swim bladder has led to a boom in illegal totoaba fishing in the past few years.

Demand for totoaba swim bladders has been driven by the belief in Chinese medicine that they are a cure to a variety of illness and diseases. Thousands of swim bladders are dried and smuggled out of Mexico, often through the United States. Fishermen receive around $4,000 for each pound of totoaba swim bladder, equivalent to half a year’s income from legal fishing activities. The practice has caused a catastrophic decline that is estimated as cutting the remaining vaquita population in half each year. The little porpoise wasn’t discovered until 1958, but is now the world’s rarest marine mammal.

However, this study proves that all may not be lost. “Small numbers do not necessarily mean the end of a species, if they have the protection they need,” Taylor said. “In conservation biology, we’re always looking for risk. We shouldn’t be so pessimistic. The sight of those three healthy calves in the water with their survivor mothers should inspire the protection they need to truly recover.”

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DNA Detectives Aid Rhinos https://www.conservationjobs.co.uk/articles/dna-detectives-aid-rhinos/ https://www.conservationjobs.co.uk/articles/dna-detectives-aid-rhinos/#respond Wed, 30 Jun 2021 15:05:35 +0000 https://www.conservationjobs.co.uk/?p=77831 Researchers have, for the first time, used unique DNA markers to provide forensic evidence for alleged poaching cases involving the Indian rhino. The project is part of the Rhino DNA Indexing System (RhODIS- India) conservation program. This database has been created to build a DNA catalogue of the existing Indian greater one-horned rhinoceros to tackle rhino poaching and assist conservation efforts for this vulnerable species.

Inspired by a similar program in South Africa, a team of scientists collected dung from 749 rhinoceros to gather vital genetic information. By analysing dung for traces of population specific genetic signals, a genetic baseline was created for rhinoceros across India and 406 unique individuals were identified.

Microsatellite markers are present in nuclear DNA, similar to a fingerprint, where each individual has its own unique genetic signature. The use of 14 markers helps to identify individuals from dung data based on unique individual rhino’s signature.

By comparing seized rhino horn samples to these specific genetic signals, the researchers could trace the rhino back to its breeding population, thus identifying trade routes and pinpointing poaching hotspots, which are notoriously difficult for traditional law enforcement to track.

“Having an allele frequency map aids in pinpointing the location of the orphan seized rhino sample to its breeding population based on genetic signatures,” commented Tista Ghosh, a member of the research team.

The forensics team at the Wildlife Institute of India were also able to match a suspected poached carcass from a protected area to a seized horn found elsewhere along the trade route in India. Occasionally, they had as little to work with as blood-stained soil, pebbles or a bullet to perform DNA profiling.

These results display the powerful abilities which this microsatellite panel has for tackling wildlife crime and providing valuable insights to the forest department. Furthermore, individual DNA matching assists in court prosecutions by providing concrete scientific evidence regarding the poaching of wild rhino, native to India.

On the significance of this method, Tista said: “Many times the seized rhino body parts are found after a long time of poaching incidence as a result of which it becomes difficult to pinpoint the location of the crime. Thus, it is important to locate such networks and have law enforcement resulting in breaking the chain of trading.”

India’s current population of greater one-horned rhinoceros’ is relatively small, at approximately 3,500 rhino individuals. Using statistical probabilities, the team calculated that 14 microsatellite markers were sufficient to be able to do individual matching across the whole range of the population.

In addition, the researchers are keen to collaborate with Nepal field teams to extend this work to the second strong hold of greater one-horned rhinoceros.

However, in the field of wildlife forensics, there are severe limitations due to the poor quality of samples, and circumstances when data could not be generated using microsatellite only. In those scenarios Tista said, of these exciting developments, “We are planning to do a mitochondrial DNA screening to look for park/state specific genetic markers and combine that data with our existing database to avoid such situations.”

The RhODIS-India marker panel is still in the process of developing an ‘allelic ladder’ (reference point) for comparisons with other laboratories. When this becomes available, this will foster greater collaboration between the global wildlife forensics community. In order to increase the size of the database, plans are already in place to carry out wider sampling across the Indian rhino’s range.

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