Green Group discussion

Rats have finally been cleared off former whaling island South Georgia. They had been preying on nests of the rare birds, which have to nest on the ground.

https://gizmodo.com/south-georgia-isl...

Humans brought their rats and cats and genocidal tendencies to islands and were devastating to all birds, especially those that lost their ability to fly because they had no predators.

We even look at the word "dodo" as stupid instead of gentle or curious:

https://www.forbes.com/sites/quora/20...

https://www.independent.ie/world-news...
Another look at the same story.

Excellent. Now they have to keep new rats from arriving.

As the stories explain, precautions will be taken.

Rats were eradicated from small Dalkey island off Dublin.
Now terns have been able to raise chicks.

https://www.irishtimes.com/news/envir...

30 billion and still going for some kind of record. According to the UN, the big rats are 2 footed, tailless, mostly hairless, definitely clueless.

Giant mice are playing the same pest /predator role and killing off albatross chicks on Gough Island. This story explains that a team sent to eradicate the mice had to cancel due to Coronavirus.

https://gizmodo.com/coronavirus-thwar...

I don't really see this - if you've got rodenticide that albatrosses won't eat, why can't you just keep spreading it? The team were missing some key personnel - whom do you need? Presumably you can all do basic cooking and first aid.

I read the Guardian article and I still don't understand it.

https://www.theguardian.com/environme...

From an earlier article:
"Only 2,000 pairs of these enormous birds (they have a 10-foot wingspan) remain, nearly all of which breed on Gough. This species relies on a breeding strategy in which parents raise single eggs every other year. This strategy is called K-selection: Species that compete for limited resources, like albatrosses, spend more time raising fewer offspring that will hopefully have a higher chance of making it to adulthood."

https://gizmodo.com/invasive-mice-see...

"The black rats weren't supposed to be there, on Palmyra Atoll. Likely arriving at the remote Pacific islet network as stowaways with the U.S. Navy during World War II, the rodents, with no natural predators, simply took over. Omnivorous eating machines, they dined on seabird eggs, native crabs and whatever seed and seedling they could find.

...
""Prior to the eradication, most of the understory of Palmyra was either bare ground—sandy soil or coral rubble—or covered in a carpet of ferns," said Ana Miller-ter Kuile, a graduate student researcher in the Young Group and lead author of a study that appears in the journal Biotropica. The rats were quick to eat seeds and young plants coming out of the ground, and they frequented the canopy as well, often nesting in the coconut palms and eating coconuts."

While wildlife thrived and tree seeds grew, the island staff were not delighted that invasive coconut palms took over, and are now uprooting them. This is an interesting read.

https://phys.org/news/2020-11-eradica...


More information: Ana Miller‐ter Kuile et al, Impacts of rodent eradication on seed predation and plant community biomass on a tropical atoll, Biotropica (2020). DOI: 10.1111/btp.12864
Journal information: Biotropica
Provided by University of California - Santa Barbara

Here's a post about Palmyra Atoll from 2018, before the proliferation of coconut became so apparent. Looks like coconut has a faster growth.

"Before removal, no seedlings of native Pisonia grandis trees were found in research plots. Immediately following removal of invasive rats, seedlings proliferated and plots had an average of 8 seedlings per square meter. For five native tree species, including Pisonia grandis, fewer than 150 seedlings were counted in the presence of rats, and more than 7700 seedlings were counted five years after rats were removed.

Lead scientist Coral Wolf from Island Conservation said: "Once rats were gone, changes became immediately apparent. We were so excited to walk into a forest stand of towering Pisonia trees and find a mat of tiny seedlings carpeting the forest floor—something that hadn't been observed at Palmyra in recent decades as far as we know."

Palmyra's tropical rainforest also provides important habitat for a native gecko, insects, crabs and other rare species. Pisonia grandis forests are reported to be in decline globally."
...
"Forty-one percent of the world's most highly threatened vertebrates are found on islands, with invasive species introduced to islands being a leading cause of extinction. Removing invasive species from islands is an effective and proven way to save our world's most vulnerable species.
To date, there have been more than 500 successful projects to remove invasive rodents from islands. The pace, scale, and complexity of these efforts are increasing in recognition of the threat invasive species pose to biodiversity."

https://phys.org/news/2018-07-percent...

More information: Coral A. Wolf et al. Invasive rat eradication strongly impacts plant recruitment on a tropical atoll, PLOS ONE (2018). DOI: 10.1371/journal.pone.0200743
Journal information: PLoS ONE
Provided by Island Conservation

https://www.islandconservation.org/bi...

"Five years after a vast rat removal operation on Acteon and Gambier islands, by an international conservation team, endangered bird populations are on the rise and still, there are no signs of rats.

In conjunction with the BirdLife International and Island Conservation, the Societe d’Ornithologie de Polynesie (SOP Manu) returned to the Acteon and Gambier island groups last month to inspect Vahanga, Tenarunga, Temoe, and Tenararo. Five years after the project was implemented, how is wildlife recovering?
...
"Once one of the most widespread birds in the Pacific—the Polynesian Ground-dove, also known as Tutururu—is considered one of the rarest birds in the world, with fewer than 200 surviving individuals. The success of the operation on Acteon and Gambier, doubled the species available habitat, and now populations are increasing from six individuals observed in 2017, to fifteen or twenty per island."

Aleutians....

https://www.islandconservation.org/se...

"Along the western edge of Alaska’s Aleutian archipelago, a group of islands that were inadvertently populated with rodents came to earn the ignominious label of the “Rat Islands.” The non-native invaders were accidentally introduced to these islands, and others throughout the Aleutian chain, through shipwrecks dating back to the 1700s and World War II occupation. The resilient rodents, which are known to be among the most damaging invasive animals, adapted and thrived in the new setting and eventually overwhelmed the island ecosystems, disrupting the natural ecological order and driving out native species.

A coordinated conservation effort that removed the rats from one of the islands formerly known as Rat Island has become a new example of how ecosystems can fully recover to their natural state in little more than a decade. The ecological rebound at newly named Hawadax Island (a return to the original Aleut name meaning “the island over there with two knolls”) extended from land to the island’s interconnected marine community. Results of a study published in Scientific Reports and led by a University of California San Diego researcher has documented the remarkable recovery."

Rats and mice are among the most invasive species in terms of cost and destruction. Here's an article assessing the whole lot.

https://phys.org/news/2021-03-us128-t...

"Native species naturally are found on the Galapagos, but can also be found elsewhere. Blue-footed boobies are a good example of a native species that many people travel to the Galapagos to see.

Introduced species have been brought over to the islands — on purpose or accidentally. On the Galapagos Islands, the most common intentionally introduced species include goats, cats and dogs. Rats are one of the most aggressive and problematic species accidentally introduced to the region.

Ships visiting the islands during the 19th and 20th centuries brought with them black and brown rats that thrived with no natural predators, Drone DJ reported. They became an invasive species.

According to Nature, "Rats and other non-native species have caused extensive damage to the Galapagos, whose unique flora and fauna evolved in isolation for millions of years."

That relative isolation may have caused many native species to lose their defense mechanisms against predators, the journal article said. Because rats reproduce quickly and eat a variety of plants and animals, they pose a particular threat to places like the Galapagos whose rich biodiversity is irreplaceable. The rodents especially threatened unhatched and young birds because they eat eggs and nestlings. They also threaten native trees by gnawing on their branches and eating their seeds, Nature reported. In fact, invasive rodent infestations are estimated to account for 86 percent of the known extinction of native wildlife on islands.

Therefore, rats have been the target of multiple eradication campaigns across the Galapagos, Nature reported. The eradication efforts were deemed "necessary" on the two Galapagos islands to protect indigenous wildlife, including frigate birds and swallow-tailed seagulls on the two islands in the Galapagos.

After a few failed manual attempts at eradication, the Galapagos National Park began deploying drones in Jan. 2019. Drones have the advantages of increased speed, efficiency and safety over manual baiting over rugged terrain, Nature and Drone DJ reported. And, they are cheaper than using helicopters, until now a favored tool in culling non-native animals."

https://www.ecowatch.com/galapagos-ra...

Not rats but stoats feature in this eradication effort. Thanks to Scots author Iona McDuff for alerting me.

"Poor wee stoats. There's a massive campaign on to eradicate them from the Orkney Islands, off the north coast of Scotland.

In case you're wondering what stoats are, they look like weasels, or mink, and in the winter the brown fur changes to white, apart from the black tail tip, to blend in with the snow. They are then described as being 'in ermine.' (See how I geeked out in 'Nature Study' lessons in primary school?)

They're common throughout Scotland, but only started appearing in the Orkneys in 2010. I've no idea how they managed that, for it's over 6 miles across rough and freezing sea between John O' Groats at the very northern tip of Scotland, to the nearest Orkney island, South Ronaldsay.

Stoats are ferocious, and can tackle prey much larger than they are. The problem is, they're wiping out important native Orkney species.

If you'd like to read the article, and see a nice picture of a stoat, click here.
https://click.mlsend.com/link/c/YT0yM...

And here's a fun fact - in Scotland, 'stoatin' aboot' (stoating about) means 'walking around'."

The stoat is in the Mustelidae family, slightly larger than the weasel, which manages to kill rabbits larger than itself. They are obligate carnivores and came from the same branch as cats, not dogs. The ferret is a cousin (domesticated and used for rabbit hunting) and the largest member in UK is the the pine marten, which kills imported grey squirrels.
The largest Mustelidae is the wolverine, which is bigger than the fisher, both living in North America.

Rats and mice as imported predators feature in this new book on birds. The good news is that when rodents were removed from Lundy Island off Devon, the puffin colony flourished. It had been reduced to a few individuals. The worry is always that people and bodies think it's not worth the effort of removing the rodents to save a handful of remnant birds - when it darn well is.

Ten Birds That Changed the World


https://www.theguardian.com/environme...

Nearly 1,000 migrating songbirds perish after crashing into windows at Chicago exhibition hall.

Eradication of bird "predators" also involves proper building lightning, window designs that don't confuse birds, and awareness of bird flight patterns.

Some places have regulations for buildings interaction with birds that apply to new buildings. The Chicago exhibition hall was built in 1957. Because of the cost, like many other buildings, its design has never been updated.

"Researchers estimate hundreds of millions of birds die in window strikes in the United States each year. Scientists with the Smithsonian Conservation Biology Institute and the U.S. Fish and Wildlife Service released a study in 2014 that put the number between 365 million and 988 million birds annually."

By 2022 the number of birds killed in building collisions is now put at 1 billion per year. Events of up to 12,000 birds have now been recorded.

https://www.yahoo.com/news/nearly-1-0...

https://www.fws.gov/story/threats-bir...

https://www.rte.ie/news/regional/2024...

"A two-year-old fox red labrador named Woody has become the latest wildlife worker on Rathlin Island off the Co Antrim coast.

Woody has been recruited to help with the world's first ferret eradication programme on an inhabited island.

Michael Rafferty, fieldwork manager with environmental group LIFE Raft explained that the island has a ferret and rat problem.

The issue is negatively impacting the ground nesting bird population and seabird colonies such as the Manx shearwaters, puffins and corncrakes.

The ferrets were originally brought to Rathlin Island in the 1970s to assist with the amount of rabbits on the island, but after this, they started to become a problem for native wildlife."

https://phys.org/news/2024-06-rat-fre...

"The findings by an international team of marine scientists, led by researchers at Lancaster University, have been published today in the journal Conservation Biology.

"We know that invasive species, such as rats, have devastating impacts on native seabird populations—they eat the eggs, chicks and even sometimes adult birds," said Dr. Ruth Dunn of Lancaster University and lead author of the study.

"It's been shown that restoration projects that remove invasive species, such as rats, are effective. However, when there are limited resources in planning island restoration projects, it is also important to know if seabird populations are restored that there will be enough fish in the sea for them to hunt and eat—especially as threats such as overfishing and climate change make fish populations more uncertain.

"Our study was the first to factor in this important consideration, and encouragingly for the remote islands we studied, we found that there are enough fish in the sea for restored populations of seabirds."
...
"The research team looked at three projected scenarios where invasive rats would be eradicated from 25 islands, and natural habitat, such as native forest and savannah, would be restored to different degrees.

Their modeling shows that if rats were removed from these 25 islands, that could result in populations of lesser noddies, sooty terns and red-footed boobies recovering to nearly 24,000 breeding pairs—an 18-fold increase."

More information: Island restoration to rebuild seabird populations and amplify coral reef functioning, Conservation Biology (2024).
https://conbio.onlinelibrary.wiley.co...
Journal information: Conservation Biology

Provided by Lancaster University

https://phys.org/news/2021-04-evidenc...

"The new study led by scientists at Lancaster University and published in the journal Current Biology shows that critical cycles of seabird nutrients flowing to coral reefs are re-established within relatively short time periods after rats are removed—even around islands that have been infested for hundreds of years.

The findings offer encouragement that rat eradication can benefit coral reefs, because these nutrient flows can bolster the health of delicate coral reef ecosystems and may improve their chances of rebounding between climate disturbance events.

Seabirds are a critically important distributor of nutrients for island and marine environments. They feed on fish often in the open ocean far from islands, and then return to islands to roost—depositing nitrogen-rich nutrients on the island in the form of guano—or poo. Some of the guano is then leached off the islands by rain and into the surrounding seas where the nitrogen fertilises corals and other marine species such as algae and sponges, boosting the food-chain.

However, over the last several centuries people introduced rats to many tropical islands through settlement, sailing between islands and shipwrecks. Rats are a very damaging invasive species, consuming the seeds of many plants, and devastating bird populations as they eat eggs, chicks, and even adults of the smallest seabird species.

Previous studies by scientists from the same research team revealed that islands with rat infestations had much smaller seabird populations than islands without rats, and as a result, there was much less nitrogen on the islands, and in the surrounding marine environments. This results in significant knock-on negative effects with less reef fish biomass, reduced ecosystem functioning, and slower coral growth on adjacent coral reefs."

More information: Current Biology (2021).
https://www.cell.com/current-biology/...
Journal information: Current Biology

Provided by Lancaster University

Tree snakes are another invasive danger.

https://phys.org/news/2024-07-brown-t...

"Brown treesnakes are not indigenous to Guam. The species arrived shortly after World War II, perhaps aboard shipping vessels. Since then, they have caused the local or total extinction of most native forest bird species.

Researchers including Haldre Rogers, a tropical forest community ecologist and conservation biologist in the College of Natural Resources and Environment have spent years conducting studies to support and inform bird conservation efforts.

Since 2007, Rogers has operated the Ecology of Bird Loss project in Guam to better understand how losing birds impacts the ecosystem and to form strategies to restore birds to the ecosystem. It has previously been suggested that while total eradication is optimal, removing the large, mature snakes—the ones big enough to eat birds—might be sufficient to allow some bird populations to recover.

Research, published on July 25 in Ecology and Evolution, shows that snakes are killing birds whether they can eat them or not, suggesting that they are routinely tackling prey that are too large for them to swallow.

"Around half of the birds that are getting killed by snakes are not actually eaten by them," said Martin Kastner, a doctoral student in the Department of Fish and Wildlife Conservation. Kastner has spent the last three years with a team in the Mariana Islands conducting the first study into the influence of both prey and predator sizes on brown treesnake predation success.

"Before this work, no one realized the extent to which snakes are unsuccessfully trying to predate birds," said Rogers. "I think we just assumed that most of the time they would be good at estimating how large a prey they would need, so it came as a big surprise to us that almost exactly half of the birds were not actually consumed."
...
""In the right context, snakes are a big part of the ecosystem. They're wonderful in the right place, but in Guam, unfortunately, they're invasive, so that's important to keep in mind," said Kastner. "We need to get rid of them if we want hope of bringing back native birds and restoring the overall ecosystem.""

More information: Martin Kastner et al, Gape‐limited invasive predator frequently kills avian prey that are too large to swallow, Ecology and Evolution (2024).
https://dx.doi.org/10.1002/ece3.11598
Journal information: Ecology and Evolution

Provided by Virginia Tech