Inbreeding in Orcas
Southern Resident killer whales, a small population of orcas living in the Pacific Ocean off the northwest coast of North America, are so isolated that they’ve taken to inbreeding, which has contributed to their decline, a new study finds. One reason for this decline is the group’s limited geographic range, which stretches between British Columbia and Oregon.
In general, killer whales begin reproducing when they’re 10 years old, hitting their reproductive prime in their early 20s. However, the Southern Resident orcas had less than half the chance of surviving through their prime years to reach 40, compared to the least inbred individuals. Additionally, females with the lowest level of inbreeding can expect to have 2.6 offspring in their lifetimes, while highly inbred females will have an average of 1.6 calves.
The number of endangered monarch butterflies that reached their winter habitat in the mountains of western Mexico dropped by 22% this season, the victims of illegal logging, habitat loss and climate change. The World Wildlife Fund Mexico reports that extreme 2022 temperatures in the United States contributed most to the decline.
Droughts, frosts and the loss of the migrating monarchs’ food source, milkweeds, across North America are also major factors. The monarchs once clustered in trees covering more than 18 hectares of forest in Michoacan state before logging, fires, drought and removal of sick or weak trees brought that number down to only around 2.5 hectares this year.
Bird Flu Kills Mountain Lions
The Eurasian strain of highly pathogenic avian influenza (HPAI H5N1) was detected in two mountain lions in Mono County in December 2022 and January 2023, according to wildlife health experts with the California Department of Fish and Wildlife (CDFW).
Millions of Fish Die – Australian River
Contractors are being hired to remove millions of rotting fish from a river in the Australian Outback after a unprecedented die-off following floods and hot weather, police said on Monday.
The fish started dying in the Darling River near the New South Wales town of Menindee on Friday. Officials say the die-off likely occurred because fish need more oxygen in hot weather, but oxygen levels in the water dropped after recent floods receded. Mass fish kills have been reported on the Darling River in recent weeks. Tens of thousands of fish were found at the same spot in late February, while there have been several reports of dead fish downstream toward Pooncarie, near the borders of South Australia and Victoria states.
Approximately 10,000 rare white crocodiles have died of starvation and thirst as Kenya’s Lake Kamnarok, Africa’s second-largest crocodile habitat, dried up during the past year.
A shift in climate has also caused many other lakes across the East African nation, as well as the rivers that feed them, to became parched landscapes.
Kamnarok’s surviving crocs have been forced to move upstream in the lake’s diminishing watershed. This is increasing their sometimes violent contacts with the human population and livestock.
A growing population of invasive brown widow spiders is wiping out native black widows in southern parts of the United States even though there seems to be enough food and space for both species to coexist. Since arriving in Florida from what’s believed to be their native Africa, the more aggressive brown widows have quickly expanded across the country, outbreeding and killing off their darker cousins.
This should be of some comfort to residents in the region since brown widow bites are far less venomous to humans than those of black widows, with symptoms usually limited to mild skin irritations.
High Seas Treaty
After almost two decades of drafting and debating, UN member states agreed on a treaty to protect the ocean’s international waters. It is key to enforcing the 30 by 30 pledge agreed to at the UN biodiversity conference in December to place 30% of Earth’s land and seas under protection by 2030.
New protected areas will limit how much fishing can be conducted, where commercial shipping can sail and where minerals are extracted from the seabed 200 meters or more beneath the surface. The main obstacle that delayed the accord was how the ocean’s living resources would be shared, such as the plants and animals that could lead to new medications and food.
More than half of native plants are under threat in the UK and Ireland
More than half of the UK and Ireland’s native plants are in decline – and invasive species now outnumber native flora.These are the stark conclusions of a 20 year research project published in Plant Atlas this week.
The report paints a bleak picture of how climate change is decimating local ecosystems in both countries.According to the Botanical Society of Britain and Ireland (BSBI), 53 per cent of native plants and 62 per cent of ancient introductions have declined since the 1950s.In contrast, 58 per cent of modern introductions have increased.
Sea Lions Decimated by Bird Flu
In a follow-up from Peru, The National Service of Natural Areas Protected by the State announced this week the death of 3,487 South American sea lions (Otaria flavescens) in seven natural protected areas of the coast, which represents 3.29% of just over 105,000 of this species that inhabits the entire country due to H5N1 avian flu virus.
Stripes to Save Birds
Painting black and white stripes on wind turbines could help prevent the hundreds of thousands of bird deaths caused each year by impacts with their blades. Most turbines are painted white to make them blend in with the landscape. But avian vision experts say that makes them nearly invisible to many bird species.
Graham Martin of the University of Birmingham and Alex Banks at Natural England say that alternative bands of black and white would create a flickering pattern that could make the turbines stand out to birds, even in low light levels. They say this would be especially beneficial in offshore wind farms because seabirds that are currently being killed by them have fewer offspring and are slower to mature.
The first batch of trees genetically engineered to grow taller and capture more carbon dioxide from the atmosphere were planted on private land in southern Georgia in an attempt to sideline restrictions on such plantings. More will soon be planted on abandoned Pennsylvania coal mines.
The San Francisco-based Living Carbon startup added three genes to the poplars to make their photosynthesis more efficient, hoping they will turbocharge the rate the trees grow wood and suck carbon dioxide from the air. While yet unproven outside of scientific settings, the trees’ prospect of helping to remove the greenhouse gas has its supporters and critics.
Humpback Whales Fight to Mate
The amazing recovery in recent years of the humpback whale population is resulting in more aggressive mating behavior among the previously gentler males. Once hunted to near extinction, Australia’s east coast humpback population alone grew from 3,700 in 2007 to 27,000 whales in 2015.
Monitoring by a team from the University of Queensland found that male humpbacks used to sing to woo females but have now increasingly turned to fighting among themselves for the right to breed.
Endangered Bird Hunted for Sport
Should endangered wild birds be hunted for sport? It sounds like an odd question to be asking in 2023, in the midst of a biodiversity crisis. Yet, at a time when many avian species in the UK are under threat of regional extinction, government data reveals falconers are permitted to hunt rare songbirds.
Permission is regularly granted to the 25 000 registered falconers in England to kill several endangered species. These include skylark, fieldfare and mistle thrush, permitting these otherwise heavily protected birds to be legally hunted. Other red-list birds permitted to be killed in falconry include dunnocks, house sparrows, lapwings, rooks, song thrushes and starlings.
In the latest finding about wildlife cognitive ability, Japanese researchers say they have found that a common fish can recognize itself in photos.
A team from Osaka Metropolitan University writes in the journal Proceedings of the National Academy of Sciences that the Labroides dimidiatus, commonly known as a cleaner fish, demonstrated the ability, but only when it could see its face and not just its body. The species had already been proven to recognize itself in mirrors. “This study is the first to demonstrate that fish have an internal sense of self,” concluded study lead author Masanori Kohda.
Whale Deaths Linked to Turkey Earthquake
A number of whales washed up dead on the northern shores of Cyprus last week. It is thought the deaths could be linked to the massive earthquakes in neighbouring Turkey and Syria.
A pod of four beaked whales were found beached in Argaka, Paphos, on Thursday. Locals managed to guide three, which were still alive, back to sea. The fourth died, according to the Cyprus department of fisheries and marine research.
A further six whales were found dead on Friday between Polis and Pachyammos. It is unknown whether some of these were the ones that had been returned to the sea the previous day.
Whales use underwater sound as their primary way to communicate and assess their environment. Ocean noise can affect deep-diving whales’ ability to navigate, find food and avoid predators. It is thought that seismic vibrations from the recent earthquakes in Turkey and Syria may have disoriented the whales.
Avian Flu – USA
It appears that the avian flu that is decimating birds across the US is spreading o other mammals. Colorado Parks and Wildlife has identified several cases of highly pathogenic avian influenza (HPAI) in free-ranging wildlife. A black bear from Huerfano County was affected by the disease in October, a skunk from Weld County was found to be positive for the disease in November, and a mountain lion that died in Gunnison County.
Avian Flu – Peru
Park rangers who have registered the death of nearly 55,000 birds in eight protected natural areas of the coast. The most affected bird species are mainly boobies, pelicans and guanays, followed by tendrils, Dominican gulls, Peruvian gulls and gray gulls. Also in Franklin’s gulls, red-headed vultures, cormorants, Humboldt penguins and others. In recent weeks, avian influenza in birds has been identified as spreading to populations of sea lions in seven marine-coastal natural protected areas, registering 585 dead sea lions.
Avian Fllu – Europe
U.N. health experts say that even though bird flu has recently been detected in minks, otters, seals, foxes and bears, they believe the current prevailing strain of H5N1 avian influenza would have to undergo significant mutation to be able to spread among humans.
Europe is currently in the grip of its worst-ever outbreak of the disease, which has led to tens of millions of poultry being culled worldwide as well as a massive death toll among wild birds in several regions. The H5N1 strain of the virus first emerged in mainland China and Hong Kong in 1996. Experts say that should it somehow manage to mutate and circulate in humans, the current flu vaccines could easily be updated to provide protection.
A giant toad discovered deep in an Australian rainforest is believed to be the largest in the world. Dubbed by forest rangers “Toadzilla,” the gargantuan amphibian weighed 2.65 kg, which is 0.05 kg heavier than a Swedish pet toad listed in 1991 as the heaviest by Guinness.
But all did not end well for Toadzilla. Because it is an invasive species in Australia, it was euthanized due to what rangers called its “ecological impact.” Most toads typically meet the same fate when found across Australia. “Potentially, cane toads like Toadzilla would lay up to 35,000 eggs. So their capacity to reproduce is quite staggering,” said park ranger Barry Nola.