Gull populations off Canada’s southwest coast have dropped by half since the 1980s, likely due to a decline in quality food, according to a new study.

But at the risk of crying wolf, researchers at the University of British Columbia looked at long-term data compiled about the Glaucous-winged Gulls (Larus glaucescens) over the past 150 years to make sure the 30-year trend isn’t a passing phase.

“The larger implications in part are to point out that using long-term information on population trends, diet and demography gives us a much richer picture of the factors potentially driving bird population trends, said Peter Arcese, the Forest Renewal British Columbia chair of conservation biology at UBC and coauthor of the study.

“The [gull] population increased into the 1980s, but that’s really only when people started monitoring birds systematically there.”

Arcese said the team focused their study on Mandarte Island — a small rocky outcropping in the Salish Sea near Vancouver Island. On that island, the population of birds had increased from 200 breeding pairs around the beginning of the 20^th century to about 2,500 breeding pairs in the 1980s. But he said this spike could be representative of the effects of the Migratory Bird Treaty Act of 1918. Prior to that, humans harvested gull eggs or hunted the birds and historical factors like the gold rushes of the 1800s could have affected populations.

The study found that even though gull populations started to recover throughout most of the 20^th century, egg clutch sizes tended to be small, and diet analysis showed a decline in food quality.

“Eventually the decline in diet reduced clutch size and began to impair the survival of young to the point that that increase could no longer be sustained,” Arcese said.

He also added that other factors like the recovery of bald eagles (Haliaeetus leucocephalus) that prey on gulls could have had an effect on the latter’s numbers. And the lack of food for gulls may only make it easier for the eagles to hunt them. “When food is short, predators are often more effective.”

A Gauge for Ecosystem Change

While Arcese said that many people often think about gulls as “garbage birds,” the birds didn’t always feed on human trash and leftovers. Much of their diet was based on so-called forage fish.

“This bird 150 years ago was a bird that fed almost exclusively on herring and other marine organisms,” Arcese said. But these fish stocks have declined drastically over the past 150 years due to human development and fishing.

“We think there needs to be focused attention on the recovery of forage fish stocks that sustain a whole host of marine organism and marine birds,” he said.

And it isn’t just gulls. The birds were chosen because their wide-ranging diet means their population dynamics are a good gauge for health of the ecosystem in general. “Because they’re generalists, and omnivores, they also tell us something about the foods available over the past 150 years,” Arcese said. “We think the gulls are riding on top of that long-term change.”

Arcese said the gull study is part of a larger work on the history of bird populations on the Salish Sea that sits roughly between Vancouver Island and the mainland of B.C. and Washington state. They have done other studies on Mandarte island looking at marbled murrelets (Brachyramphus marmoratus) and western grebes (Aechmophorus occidentalis), which have declined by 90 percent since the 1950s and 1970s, respectively. But while the historical information on the numbers of these birds is often fragmented, they have much better information on gulls. This is necessary, he stresses, because in order to create working conservation and management plans, it’s necessary for governments and conservationists to know what the situation was like in the past.

“It’s that long term perspective that we feel is essential if someone is going to be able to create a reliable and defensible long term conservation plan,” he said. “When we talk about restoring ecosystems, we need to know where we come from. You can’t know what’s going on by looking at the past 20 years.”

Scientists are calling for an emergency plan to protect the fauna of Madagascar after a fungal disease that has laid waste to vast populations of amphibians across the world has been detected for the first time on the unique island ecosystem.

“This is sad news for amphibian-lovers around the world,” said Dirk Schmeller in a release. Schmeller is from the Helmholtz Centre for Environmental Research (UFZ) and was involved in analyzing the samples. “Firstly, it means that an island that is home to a particularly high number of amphibian species is now at risk. Several hundred species live only on this island. And, secondly, if the pathogen has managed to reach such a secluded island, it can and will occur everywhere.”

Researchers from UFZ and the Braunschweig University of Technology in Germany and others have proposed an emergency plan involving probiotic treatments, monitoring the spread of the fungus and the construction of amphibian breeding stations in the journal Scientific Reports.

The fatal chytrid fungus Batrachochytrium dendrobatidis and the resulting chytridiomycosis pandemic have decimated populations of salamanders, toads and frogs in the U.S., Central America and Australia. The disease is now poised to cause destruction on nearly 290 species of amphibians found nowhere else on the world as well as a further 200 frog species thought to live in the island country that have not yet been classified by scientists.

Boophis quasiboehmei is from the Ranomafana National Park in Southeast Madagascar. The appearance of a deadly fungus in the African country could affect 290 species of amphibians unique to the island.Image Credit: Miguel Vences/TU Braunschweig

The fungus operates by attacking the skin amphibians use to breathe. It has been confirmed in more than 500 species of amphibians and is thought to be able to affect all species.

For the study, researchers looked at samples from more than 4,000 amphibians taken from 50 sites across Madagascar since 2005. Four frog samples from 2010 from the Mantidactylus genus and a Mascarene frog (Ptychadena mascareniensis) sample taken in 2011 tested positive for the disease while chytrid fungus showed up in five regions sampled between 2013 and 2014.

The Mascarene frog sample from 2011 was taken from a particularly remote location in the Makay massif—a mountain range in southeastern Madagascar. It gives scientists some hope that the disease found there could be from a previously undiscovered native strain, meaning that the amphibians on the island may have developed some resistance to the disease.

But the researchers won’t know until the disease is analyzed.

“Luckily, there have not yet been any dramatic declines in amphibian populations in Madagascar,” Schmeller said. “However, the pathogen appears to be more widespread in some places than others. Madagascar may have several strains of the pathogen, maybe even the global, hypervirulent strain. This shows how important it is to be able to isolate the pathogen and analyze it genetically, which is something we haven’t yet succeeded in doing.”

The researchers are speaking with the African country’s government with the idea of builing more breeding stations apart from the two already under construction in order to act like arks in case some species are extirpated from the wild. They are also hopeful that the disease could be fought with the help of probiotic skin bacteria.

“The decline in Madagascan amphibians is not just a concern for herpetologists and frog researchers,” said Franco Andreone from the International Union for Conservation of Nature (IUCN) and one of the coauthors of the study. “It would be a great loss for the entire world.”

Florida’s state wildlife agency has created a draft plan to manage 60 species of mammals, birds, reptiles, amphibians, fish and other aquatic life.

The Imperiled Species Management Plan released last week by the Florida Fish and Wildlife Conservation Commission mixes conservation measures targeted towards specific species as well as broader measures that look to conserve or improve habitats that affect a number of different plants and animals.

“Florida has a diversity of imperiled species, from the American oystercatcher with its striking black and white plumage and bright orange bill, to the Santa Fe cave crayfish that lives entirely in below-ground aquatic caves,” said Laura Barrett, the coordinator of the state agency’s new plan, in a press release.

The key ringneck snake is one of the 60 species included in a new draft plan for the conservation of 60 species.
Image Credit: Kevin Enge, Florida Fish and Wildlife Conservation Commission

“With this plan, the FWC invites our many partners and the public to play prominent roles in conservation of imperiled fish and wildlife,” she continued. “Effective long-term stewardship of 60 species in this rapidly growing state requires all of us to work together on critical issues such as species monitoring, habitat conservation and education, and outreach efforts.”

Of the 60 species the plan looks at, 37 will be continued to be listed as threated in the state — five as species of special concern, three species that are listed federally on the Endangered Species Act and another 15 that are being removed from the state’s imperiled species list.

The plan is open for public comment through the agency’s website through March 13.

The following species are included in the plan:

Mammals: Big Cypress fox squirrel, Eastern chipmunk, Everglades mink, Florida bonneted bat, Florida mouse, Homosassa shrew, Sanibel Island rice rat, Sherman’s fox squirrel and Sherman’s short-tailed shrew.

A limpkin and chick. The limpkin is one of the 60 species included in a new draft plan for the conservation of 60 species.
Credit: Jack Rogers, Florida Fish and Wildlife Conservation Commission

Birds: American oystercatcher, black skimmer, brown pelican, Florida burrowing owl, Florida sandhill crane, least tern, limpkin, little blue heron, Marian’s marsh wren, osprey (Monroe County population only), reddish egret, roseate spoonbill, Scott’s seaside sparrow, snowy egret, snowy plover, Southeastern American kestrel, tricolored heron, Wakulla seaside sparrow, white-crowned pigeon, white ibis and Worthington’s marsh wren.

Reptiles: Alligator snapping turtle, Barbour’s map turtle, Florida brown snake (lower Keys population only), Florida Keys mole skink, Florida pine snake, Key ringneck snake, Peninsula ribbon snake (lower Keys population only), red rat snake, rim rock crowned snake, short-tailed snake, striped mud turtle (lower Keys population only) and Suwannee cooter.

Amphibians: Florida bog frog, Georgia blind salamander, gopher frog and Pine Barrens treefrog.

Fish: Atlantic sturgeon, blackmouth shiner, bluenose shiner, crystal darter, Key silverside, harlequin darter, Lake Eustis pupfish, mangrove rivulus, saltmarsh topminnow and Southern tessellated darter.

Corals: Pillar coral.

Crustaceans: Black Creek crayfish and Santa Fe cave crayfish.

Mollusks: Florida tree snail.

While prehistoric turtles may have been fast enough to win the race against climate change, a new study shows that habitat loss and other human pressures may put serious obstacles to stop them from making a repeat performance in the future.

Scientists from the University of Florida discovered tropical turtle fossils from the new genus Gomphochelys in modern day Wyoming that indicate the turtles moved north as the climate warmed up.

“We knew that some plants and lizards migrated north when the climate warmed, but this is the first evidence that turtles did the same,” said Jason Bourque in a release. Bourque is a paleontologist at the Florida Museum of Natural History at UF and the lead author of the study that appeared this week in the Journal of Vertebrate Paleontology.

The authors believe about 56 million years ago during a peak in global temperatures called the Paleocene-Eocene Thermal Maximum, the turtles migrated around 500-600 miles to the north along with a number of other plants and animals.

But some modern day turtle species facing pressures from habitat loss and other human-caused problems may become extinct before they can make a similar northwards exodus.

“If global warming continues on its current track, some turtles could once again migrate northward, while others would need to adapt to warmer temperatures or go extinct,” Bourque said.

Among modern species that could have a difficult time migrating is the Central American river turtle (Dermatemys mawii), modern day descendants of Gomphochelys and one of the most endangered turtles in the world. According to co-author Jonathan Bloch, a Florida Museum curator of vertebrate paleontology, the turtles would have to navigate a complicated series of rivers and other natural habitat currently in jeopardy.

“If you look at the waterways that turtles would have to use to get from one place to another, it might not be as easy as it once was,” Bloch said. “Even if the natural response of turtles is to disperse northward, they have fewer places to go and fewer routes available.”

Way before we had TV shows or manufactured board games, bowhunting may have been the pastime that brought communities together and marked individual prestige in societies.

New archaeological evidence suggests that some early agricultural communities may have collectively focused on hunting as a pastime — similar to its current role in society.

“Hunting was an element of social cohesion,” Xavier Terradas said, in Spanish, of a culture that existed in modern day Spain around 7,200 to 7,400 years ago. Terradas is an archaeologist with the Spanish National Research Council and a coauthor of the paper published recently in the Journal of Archaeological Science.

Neolithic wooden artifacts like this one were preserved for more than 7,000 years and show that humans may have used hunting as a form of social cohesion.
Image Credit: Spanish National Research Council

La Draga, a Neolithic site in Catalonia, Spain where Terradas worked, revealed a number of important archaeological artifacts from the period including full wooden bows that had been preserved under water that has receded more recently.

“The bows recovered in La Draga, besides being unique material documentation of early Neolithic archery and hunting technology, become part of the earliest archaeological evidence available on the social role of hunting in the first farming societies, especially in order to evaluate structural aspects such as economic specialization, division of labor and the nature of resource access,” Terradas said in a release.

The archaeologists also uncovered evidence that the people who lived there primarily drew their nutrition from agriculture and domesticated animals. Numerous seeds were found as well as the bones from cattle.

“Based on the bones, we can tell whether the animals are domestic or hunted,” Terradas said.

Researchers also discovered bones of hunted prey like deer, wild goats and other animals, but they estimated that only about 3 percent of the diet of the Neolithic people in this area actually came from hunted animals.

“Hunting is not related to subsistence but other elements,” Terradas said the authors concluded. They found a variety of projectiles made from different materials like rock, wood and bone, but Terradas said that there wasn’t much armed conflict between different groups of humans around that time. Instead, the study found that prestige was one of the main drivers of this form of social hunting and was linked to the type of animals hunted and prey distribution.