By John R. Platt
It takes a lot of effort and more than a little bit of luck for researchers like André Raine to get to the remote mountaintops of Kauai, where they're working to save endangered Hawaiian seabirds from extinction.
Raine holding a Hawaiian petrel chick. Courtesy Kaua'i Endangered Seabird Recovery Project<p>So, unfortunately, do several species of invasive predators — including feral cats, black rats and feral pigs — that have put these ground-nesting birds, and so many other native Hawaiian species, on the fast track toward extinction.</p><p>"People are always really surprised by this," Raine said, "but it doesn't matter how remote the area, or how apparently inhospitable it is to predators like cats. You're going to find cats and rats and pigs in these areas. There wasn't a single site that we work in that doesn't have all these predators, busy eating the birds."</p>
An endangered chick in the mouth of a feral cat. Courtesy Kaua'i Endangered Seabird Recovery Project<p>Like many island endemics, Hawaii's bird species grew up without mammalian predators, so they're ill-adapted to the teeth and claws that arrived with human society. The cats descended from housecats, while pigs escape from agricultural sites and rats descended from stowaways on ships.</p><p>That's why the Kaua'i Endangered Seabird Recovery Project has spent the past nine years constructing fences and establishing other predator controls — work that is proving essential in giving these native birds a chance.</p><p>The first step in controlling predators is quantifying the threat.</p><p>According to a paper Raine and his colleagues published earlier this year in <a href="https://wildlife.onlinelibrary.wiley.com/doi/full/10.1002/jwmg.21824" target="_blank">The Journal of Wildlife Management</a>, introduced predators killed at least 309 endangered seabirds at six monitored breeding colonies between 2011 and 2017. That's quite a blow for each of these endangered species.</p><p>"Newell's shearwaters and Hawaiian petrels have suffered catastrophic declines over the last few decades," Raine said. "Any chick that's lost in the population is one that we can't afford to lose."</p>
Hawaiian petrel. © Ken Chamberlain, some rights reserved (CC-BY-NC). Via iNaturalist.<p>The researchers took on the sad task of collecting the dead and examining the wound patterns to determine which type of predator made the kill.</p><p>Rats, it turned out, killed the most — more than 50% of mortalities — usually from entering the birds' rocky burrows and eating eggs and chicks. That dramatically slows recovery efforts, but the research shows that adult birds who've lost their chicks returned to the same burrows the following year to try again.</p>
Fence Me In<p>Over the past decade, the Kaua'i Endangered Seabird Recovery Project and its many organizational partners have concentrated on establishing predator controls at six of their seven regularly monitored seabird breeding sites.</p><p>Again, this isn't easy to accomplish in these remote, rarely visited locations. Materials must be flown in, ungulate-proof fences built, other traps set, and pig-hunting expeditions organized. All of it must be accomplished and maintained in precarious territory full of wet vegetation, narrow ridgelines and steep canyon walls.</p><p>To make things even more difficult, the human visitors must leave the habitat as undisturbed as possible.</p><p>"If you start making trails in these areas, then you're basically just opening them up to the hordes of predators that are out there," Raine says.</p><p>But the hard work pays off.</p><p>According to the paper, fences and other controls not only keep the invasive predators out, they give the birds the opportunity to thrive.</p><p>The research team used seven years data from the six sites, from before and after predator controls were established, and projected striking results for the future of the two seabird species.</p><p>The first model looked at what would happen to each site without predator controls. It was a disaster — mostly due to cats. "We ran that for 50 years, and we found that all of the colonies dwindle toward extinction."</p><p>The paper, in what Raine acknowledges as gallows humor, calls this the <em>CATastrophe</em> model.</p><p>The second modeling approach incorporated data from successful breeding that took place after more extensive predator controls (fences and traps) were put in place. "We found that the populations increased over those 50 years," Raine said. Under the model, which was based on 2017 population growth rates at sites with predator controls, most sites would see a 50-60% increase over the 50-year projection, while one site more than doubled.</p><p>"It really does show that if you remove the predators, the birds will begin to recover."</p>
The introduction of invasive species has been the primary cause of plant and animal extinctions over the past 500 years, a new study from University College London's (UCL) Center for Biodiversity and Environment Research found.
The study, published Monday in Frontiers in Ecology and the Environment, looked at 953 extinctions since 1500 and found that 126 of them, or 13 percent, had been caused entirely by alien species, while 300 were caused partly by the arrival of new species, according to a UCL press release published by EurekAlert!
EcoWatch Daily Newsletter
By Jason Bittel
My wife and I built a house two years ago on a few acres of woodland outside of Pittsburgh. The backyard is full of maples, poplars, briars and common spicebush. Two-lined salamanders and grumpy-looking crayfish wade among the rocks in the small stream that runs down the edge of the property. Deer, raccoon and opossum tracks appear regularly in the snow and mud. Sometimes, my trail-cam even catches a pair of gray foxes as they slink through the night.
The Genal Valley in Southern Spain is famous for its sweet chestnuts, and that could give the economically struggling region a huge boost as vegans and vegetarians in Northern Europe develop a taste for Castanea sativa. But a new threat is putting the valley's reputation, and future, at risk, BBC News reported Tuesday.
"We've lost at least 30% of our usual production," farmer Julio Ruiz told BBC News. "It is all the fault of a small wasp."
Tasmania's swift parrots can't catch a break. Logging has reduced their preferred blue gum breeding habitat by a third in the past 20 years. Sugar gliders, a kind of nocturnal possum introduced in the 1800s, are gobbling up female parrots at an alarming rate. And now, The Guardian reported Tuesday, scientists have found that the skewed male-to-female ratio is changing the mating habits of the endangered species in a way that puts its survival further at risk.
Earlier this week, a Florida man caught and killed a 17-foot, 5-inch female Burmese python in the Miami-Dade County Everglades.
The South Florida Water Management District (SFWMD) praised Homestead-based hunter Kyle Penniston's record-setting catch for its Python Elimination Program. Weighing 120 pounds, she was certainly a big one and she even bit Penniston's hand before she was shot on Monday night, according to his Facebook post.
They have displaced American alligators as the Everglades' top predators and have been found responsible for putting a dent in the populations of raccoons, opossums and bobcats, according to The National Parks Traveler.
Researchers at the University of Hawaii at Manoa and the state of Hawaii's Division of Aquatic Resources (DAR) have developed an innovative method of removing invasive macroalgae that can smother coral reefs, the University of Hawaii reported Aug. 9.
An invasive tick species was found to have spread to an eighth state Tuesday, when the Maryland Department of Natural Resources announced one was found on a deer in Washington County, The Washington Post reported.
Following a £10 million ($13.5 million) eradication scheme and nearly a decade of work, South Georgia was officially declared rodent-free on Tuesday, the first time since humans arrived on the island more than 200 years ago.
The British territory is one of the world's last great wildlife areas. There you'll find 98 percent of the world's Antarctic fur seals, half the world's elephant seals and four species of penguins—including King Penguins with around 450,000 breeding pairs. The birdlife includes albatrosses, prions, skua, terns, sheathbills and petrels.
By Mary Hoff
What should we be thinking about when we think about the future of biodiversity, conservation and the environment? An international team of experts in horizon scanning, science communication and conservation recently asked that question as participants in the eighth annual Horizon Scan of Emerging Issues for Global Conservation and Biological Diversity. The answers they came up, just published in the scientific journal Trends in Ecology & Evolution and summarized below, portend both risks and opportunities for species and ecosystems around the world.
"Our aim has been to focus attention and stimulate debate about these subjects, potentially leading to new research foci, policy developments or business innovations," the authors wrote in introducing their list of top trends to watch in 2017. "These responses should help facilitate better-informed forward-planning."
1. Altering Coral Bacteria
Around the world, coral reefs are bleaching and dying as ocean temperatures warm beyond those tolerated by bacteria that live in partnership with the corals. Scientists are eyeing the option of replacing bacteria forced out by heat with other strains more tolerant of the new temperatures—either naturally occurring or genetically engineered. Although the practice holds promise for rescuing or resurrecting damaged reefs, there are concerns about unintended consequences such as introduction of disease or disruption of ecosystems.
2. Underwater Robots Meet Invasive Species
If you think getting rid of invasive species on land is a challenge, you haven't tried doing it in the depths of the ocean. Robots that can crawl across the seafloor dispatching invaders with poisons or electric shock are being investigated as a potential tool for combating such species. The technology is now being tested to control crown-of-thorns starfish, which have devastated Great Barrier Reef corals in recent years and invasive lionfish, which are competing with native species in the Caribbean Sea.
3. Electronic Noses
The technology behind electronic sensors that detect odors has advanced markedly in recent years, leading biologists to ponder applications to conservation. Possibilities include using the devices to sniff out illegally traded wildlife at checkpoints along transportation routes and to detect the presence of DNA from rare species in the environment.
4. Blight of the Bumblebees
We tend to think of pollinating insects as our ecological friends, but in the wrong place nonnative bees can spell trouble instead by competing with native insects, promoting reproduction in nonnative plants and potentially spreading disease. And they're doing just that, thanks to people who transport them internationally for plant-pollination purposes. Out-of-place bumblebees are already spreading through New Zealand, Japan and southern South America, and there is concern they could do the same in Australia, Brazil, Uruguay, China, South Africa and Namibia.
5. Microbes Meet Agriculture
Select bacteria and fungi are emerging as potential agricultural allies for their ability to help kick back pests or stimulate growth in crops. As research advances in this area, questions are being raised about potential implications for nontarget species, ecosystems, soils and more.
Bumblebees imported to pollinate crops are a growing threat to native pollinators around the world. iStock