Thursday, July 12, 2018

New study finds rat eradication improves fisheries around islands

Rat on palm. Credit Island Conservation, USFWS
If the rat eradication of Lehua Island ends up being successful, it could result in a more productive nearshore fishery.

Which is ironic, in that many of those fighting the eradication program were fishermen.

A new study in the journal Nature says that when rats kill off seabirds on islands, it means those birds are no longer pooping in the nearshore waters, fertilizing reefs. And that means fewer fish on those reefs.

This study was done in the Chagos Archipelago, where some islands have rats and others are rat-free. Researchers looked at both the fertility of the land on those islands and the productivity of their reefs, where erosion from the land would carry nutrients like bird-poop-sourced nitrogen.

The Chagos are atolls and reefs just south of the Equator in the Indian Ocean. Their ownership is disputed between Great Britain and Mauritius. One is Diego Garcia, which houses a U.S military base.

The results of the research were clear, said the authors, who are from Australian, British, Danish and Canadian research institutions.

On islands without rats, seabird density as well as nitrogen deposits were hundreds of times higher. Yes, hundreds: 250 to more than 700 times higher.

Those rat-free islands had reefs that had 48 percent more biomass of "macroalgae, filter-feeding sponges, turf algae and fish."

The researchers looked specifically at damselfish, and found that they both grew faster and had higher total biomass on the rat-free islands.

The theory, then, is that seabirds feed in the open ocean, deliver bird poop to the islands, and that the islands then feed the nearshore waters, which makes the waters more productive and capable of producing more fish.



"Rat eradication on oceanic islands should be a high conservation priority as it is likely to benefit terrestrial ecosystems and enhance coral reef productivity and functioning by restoring seabird-derived nutrient subsidies from large areas of ocean," the authors wrote.
Vampire mouse victim. Credit USFWS

Rats are not the only problems on islands. On Midway Atoll, near the western end of the Hawaiian archipelago, mice began eating seabirds after rats were removed from the islands there. The case of the vampire mice, which chewed into the necks of Laysan albatross, is reviewed here.

On other islands, the mice even seemed to be getting bigger on their diets of eggs and bird flesh. The Washington Post was among the many international publications that picked up the vampire mouse story.

All that said, rodents mainly go after eggs and chicks of nesting seabirds. That was the case at Lehua Island. Here is a description of the situation on the little island north of Ni`ihau before an application of a rodenticide to try to wipe out the rats.

"We found Wedge-tailed Shearwater and Red-tailed Tropicbird eggs broken open, the edges gnawed, the insides consumed. Tiny seabird chick bodies were commonplace–pulled out of burrows and half eaten. This was particularly true for the diminutive Bulwer’s Petrel–the vast majority of Bulwer’s Petrel burrows we found had bits and pieces of chick inside," wrote Andre Raine, Project Manager for the Kauai Endangered Seabird Recovery Project.



A couple of months after the 2017 rat eradication effort at Lehua, Raine said he could clearly see the difference:

"Fat, healthy Wedge-tailed Shearwater chicks shuffled about in their burrows looking like animated fuzzballs. One of our burrow cameras showed a Bulwer’s Petrel chick exercising outside its burrow and actually fledging – a great omen, as this is something we have never recorded on our cameras in previous years," he wrote.

Most, but not all the rats were killed off at Lehua, and wildlife crews were back this year with rat-hunting dogs to try to kill off the survivors and protect the island's nesting seabird population.

And the island's coastal reefs and fisheries.
The removal of rats from islands is a major conservation effort. It has been done successfully at islands in Hawai`i like Mokoli`i off O`ahu and Mokapu off Molokai. When it was accomplished at Palmyra Atoll south of the Hawaiian Islands, it had the unintended effect of killing off the disease-causing Asian tiger mosquito, which had depended on rats for blood meals. 

© Jan TenBruggencate 2018

Sunday, July 8, 2018

Drink coffee, live longer. It seems strange, but the science is compelling.


So what's with the health benefits of coffee?

New studies suggest you will live longer drinking coffee than from taking vitamins, eating good fruits and engaging in the latest "miracle diet" craze.

It's not entirely clear why. Its not the caffeine, because even decaf coffee has the impact of reducing mortality by statistically significant amounts.

One British study released this month followed half a million people over 10 years, and found not only that coffee drinkers live longer, but that the more coffee you drink, the better your chances of a longer life than those who drink less.

The study is entitled "Association of Coffee Drinking with Mortality by Genetic Variation in Caffeine Metabolism." It was published in the journal JAMA Internal Medicine, a publication of the American Medical Association, by authors are Erikka Loftfield, Marilyn Cornelis, Neil Caporaso, Kai Yu, Rashmi Sinha and Neal Freedman.

The study was designed to look into whether drinking a lot of coffee is a problem for people with genetic issues with caffeine metabolism, but it found that everyone—including those whose caffeine metabolism was faster or slower—had reduced mortality if they drank coffee.

This isn’t entirely new. There have been previous studies linking coffee to better longevity and to reduced rates of various diseases. That helped lead to the recommendation that up to 40 ounces of coffee (five 8-ounce cups) can be part of a healthy diet, from the 2015 report of the U.S. Dietary Guidelines Advisory Committee.

This new study is a massive study using the more than 9 million members of the UK Biobank. This study targeted 503,000 volunteers—excluding those who were pregnant, or whose coffee or nicotine intake information was incomplete. It looked at those who drink ground coffee, instant coffee and decaffeinated coffee. The average age going into the study was 57, and there were slightly more women than men. The researchers followed them for 10 years, during which time more than 14,000 of them died

People lived longer, even if they drank decaf—so it's something in the coffee or the coffee drinking, and not just the caffeine. "These findings suggest the importance of noncaffeine constituents in the coffee-mortality association and provide further reassurance that coffee drinking can be a part of a healthy diet," the study's authors write.

The authors looked at details of participants' smoking, as well as sex, weight, exercise, race, education and how much they also drank tea (it is a British survey, after all). A fifth were non-coffee-drinkers.

Ground coffee was a little healthier than instant and decaf, but they were all better than none. The study found that sex, age, weight and previous health issues did not make much difference in the outcome.

The study 's conclusion ends with this key message: "Our results provide further evidence that coffee drinking can be part of a healthy diet and may provide reassurance to those who rink coffee and enjoy it."

An earlier study of 400,000 people was published in 2012, in an edition of the New England Journal of Medicine. It had similar results. The study was entitled "Association of Coffee Drinking with Total and Cause-Specific Mortality," and was by Neal D. Freedman, Yikyung Park, Christian C. Abnet, Albert R. Hollenbeck, and Rashmi Sinha. Freedman and Sinha were authors of both papers that we discuss here.

They followed 230,000 men and 170,000 women aged 50 to 71 over 13 years, during which period about 50,000 of them died. The study found that people who drink several cups of coffee daily have lower mortality—they don't die as early as ones who don't drink coffee or who drink less coffee.

This is particularly noteworthy—and strange—because coffee drinkers tend to make bad lifestyle choices:

"As compared with persons who did not drink coffee, coffee drinkers were more likely to smoke cigarettes and consume more than three alcoholic drinks per day, and they consumed more red meat. Coffee drinkers also tended to have a lower level of education; were less likely to engage in vigorous physical activity; and reported lower levels of consumption of fruits, vegetables, and white meat. However, coffee drinkers, especially women who drank coffee, were less likely to report having diabetes. About two thirds of coffee drinkers reported drinking predominantly caffeinated coffee.

Still, according to both studies, if you drink three to five cups of coffee a day, even decaffeinated coffee, you're roughly 10 percent less likely to die in a given period.

What the heck is going on? Everybody knows about the caffeine, but if the decaf drinkers get the same protective effect (which may mean that caffeinated soft drinks don't do the same thing, incidentally) what's causing the reduce mortality?

Well, it turns out there are about 1,000 other compounds in coffee. So it might be one or more of those things.

The authors point out that they can't prove the coffee causes the health effect. It might be that something else about coffee drinkers is making them less likely to die as soon.

If it is not caffeine having an effect, maybe it's antioxidants, the authors of the 2012 paper suggest.

"Coffee contains more than 1000 compounds that might affect the risk of death. The most well-studied compound is caffeine, although similar associations for caffeinated and decaffeinated coffee in the current study and a previous study suggest that, if the relationship between coffee consumption and mortality were causal, other compounds in coffee (e.g., antioxidants, including polyphenols) might be important.

There's also a 2017 study in the Annals of Internal Medicine of coffee drinkers in 10 European countries. It had similar results: " Coffee drinking was associated with reduced risk for death from various causes. This relationship did not vary by country." 

Still, this research isn't entirely straightforward. This article from the Mayo Clinic suggests that while there may be health benefits from coffee, there are also risks for some folks. 
Oh, and taking vitamins and supplements? One study says "the results from controlled trials are dismal."
Another, on antioxidant vitamins in heart health says: "After an initial enthusiasm for antioxidants in the secondary prevention of cardiovascular disease, recent reports from of several large randomized trials have failed to show any beneficial effects." 
The takeaway seems to be that it's healthier to eat a good diet with lots of fruits and vegetables than to take supplements to make up for a bad diet. But also, that there might be some benefit to having a couple of cups of coffee with those leafy meals.
© Jan TenBruggencate 2018

Friday, July 6, 2018

Kīlauea: Dramatic, long-term changes continue. Catastrophic event possible but unlikely.


It is tough to grasp the enormous changes going on at Kīlauea volcano, including the impact on the prized national park as well as the catastrophic impacts on downslope residents.

(The view at right is from Volcano House. If you've looked over Kīlauea from this site, you'll recognize how completely different it looks now. The image is from an automated National Park Service camera.)
In the day-to-day news cycle, we tend to use a tight focus on what has been destroyed lately--the hundreds upon hundreds of lost homes, the thousands of acres of forest gone, the loss of transportation systems and the destruction of the Jaggar Museum--but scientists at the Hawaiian Volcano Observatory recently took a wider look, and the future doesn't look bright.

The U.S. Geological Survey report is entitled Volcanic Hazard at the Summit of Kīlauea, June 29, 2018 Update.
The Kīlauea caldera is collapsing at two to three inches daily, dramatically changing the look of the landscape. The lava lake has dropped 1,000 feet from its high. The parking lot at Halema`uma`u has been torn up like a sheet of paper, and it is covered by ash and rocks that have been ejected from the firepit.

If you remember the Halema`uma`u overlook, remember it well. It has now been closed since 2008, and if you ever see it again, it will look very different. The crater, for example, is four times as big as it was.

For the next few months, we can anticipate more earthquakes, ground cracking, ash plumes, vog and large scale deformation as Halema`uma`u engulfs more and more of Kīlauea Crater. It may eventually take up all of what we now know as the crater.

A sudden, massive, severely damaging collapse is considered possible, although unlikely. New lava fountains hundreds of feet high are possible. So is an earthquake much bigger than the ones felt recently.

"Strong earthquakes can occur at any time, and the risk of these events is larger now due to ongoing stress changes in and around the caldera. These earthquakes will not necessarily occur during swarm seismicity or in association with (collapse-explosion) events, may be large, and may happen outside of the caldera," the report says.

The only good news in this scenario is that if a massive, destructive collapse of the caldera occurs, there ought to be some notice of it:

"…Large-scale hazardous caldera collapse is a possible future outcome, although it is considered to be very unlikely and should be preceded by detectable warning signals. HVO should recognize these warning signs by direct observation and instrumental monitoring and, should they be detected, will alert authorities and the public."
That said:.

"The most likely course of activity for the immediate future at the summit of Kīlauea Volcano is continued subsidence of the caldera floor, episodic slumping into Halema`uma`u, felt moderate-sized earthquakes, and small ash plumes. The duration of this activity may be related to the duration of the (Lower East Rift Zone) eruption but cannot be confidently predicted," the USGS says.

In short, the most likely scenario is that we keep seeing what we’ve been seeing for the past couple of months. The less likely scenario is that it gets worse.

You can keep track of the technical details of the eruption at the USGS Hawaiian Volcano Observatory website

Another great resource is the lyrical narratives of retired Hawai`i Volcanoes National Park ranger Bobby Camara, Dispatches from Volcano

© Jan TenBruggencate 2018

Thursday, June 28, 2018

New book on Breadfruit: Make it part of your agroforest


It's no surprise that the British sailed around the world, twice, to collect breadfruit.

The ulu is that important a crop. Rich in nutrients, versatile, drought-resistant and darned easy to farm. You just plant them once, and then harvest fruit for the rest of your life.

That work of food production in the tropics and subtropics is going to get easier still with the guidance from Craig Elevitch and Diane Ragone's new volume, Breadfruit Agroforestry Guide: Planning and Implementation of Regenerative Organic Methods. Elevitch is Director of Agroforestry Net and Ragone is director of the Breadfruit Institute at the National Tropical Botanical Garden.

Their new book is available as an ebook from the National Tropical Botanical Garden website or in print for $19.95 at Amazon. 

The 72-page volume will be useful to home growers, but it's designed for agricultural professionals and extension agents, and it's an unabashed paean to the tropical and subtropical tree in complex food production systems.

The mission of the authors is not only to point up the value of breadfruit as a species, but to celebrate its role in a food forest—as part of an agroforest. Traditional Pacific societies grew breadfruit as part of a forest garden that might include taro, sugar cane, ti, banana, kava, noni and many other crops.

They argue that such a system doesn't require external fertilizers and buffers the impacts of fluctuation in markets for single crops. Multi-story agroforestry captures carbon in the soil, protects plants from the wind and reduces moisture loss.

The National Tropical Botanical Garden has a research agroforestry breadfruit garden at its McBryde Garden on Kaua`i. And it has a collection of about 150  breadfruit varieties at Kahanu Garden on Maui and at McBryde.


There are many varieties of breadfruit. The traditional Hawaiian seedless variety is just one. Others fruit at different times, produce crops that taste different, and some have seeds that can be eaten like chestnuts. 

Trees product a hundred to several hundred fruit annually, often in two seasons. The fruit is edible at any stage. Unripe fruit can be cooked and eaten as a vegetable; soft ripe fruit are eaten as a starch, and they can be baked, fried or used in any number of dishes. 

I visited an island in the Solomons where ripe breadfruit was dried for use in the season when they weren't available fresh. Other Pacific cultures preserve them underground. But they'll last a while on your kitchen shelf, and refrigeration works, too.

The book was funded by Patagonia Provisions, the Hawai`i Department of Agriculture, Kauai Office of Economic Development, and Western Sustainable Agricultural Research and Education. Its publishers are the Breadfruit Institute and Permanent Agriculture Resources.

The same authors in 2013 produced what works as a companion volume: Breadfruit Production Guide: Recommended practices for growing, harvesting, and handling. You can download that one free here

But actually buying the books--search for them at Amazon--helps support the programs Ragone and Elevitch run.

Here's what the authors had to say, from the press release on the new book:
Ragone: “Breadfruit has been grown sustainably since humans began cultivating it thousands of years ago. It’s vital that we revive centuries of indigenous knowledge and traditional methods into a modern context. Doing so will help breadfruit thrive and support communities for many generations.”

Elevitch: “This is a crucial time for the future of breadfruit and island agriculture in general. Given that the single-crop plantation model with high chemical inputs leads to declining soil fertility and plant health, growers are now developing models for breadfruit production rooted in traditional methods.”

© Jan TenBruggencate 2018

Monday, June 11, 2018

Hawai`i data shows CO2 at record levels in atmosphere: and growing faster than ever


Annual CO2 growth rate. Source: NOAA, Scripps
Carbon dioxide levels in the atmosphere continue to grow at a record rate, promising that climate change will continue long beyond our lifetimes.

That's from data collected in Hawai`i—at the Mauna Loa Observatory, which has been collecting atmospheric CO2 data for 60 years. 

The Scripps release on the milestone is here.

In May, those levels reached a record high of 411.31 parts per million.

The latest tally was released last week by scientists from Scripps Institution of Oceanography at the University of California San Diego and NOAA.

And despite international efforts to control emissions, they appear to not be effectively under control. The level of emissions is not only continuing to grow, but it's growing faster. It was growing at 1.5-1.6 parts per million in the 1980s through 1990s, but during the past 10 years has been growing at 2.2 parts per million.

“Many of us had hoped to see the rise of CO2 slowing by now, but sadly that isn't the case. It could still happen in the next decade or so if renewables replace enough fossil fuels,” said Scripps CO2 program director Ralph Keeling, whose father Charles Keeling started the Mauna Loa CO2 program in 1958.

But while it's possible to reverse the growth trend in CO2, for species of all kinds, including humans, the future isn’t bright.

“Today's emissions will still be trapping heat in the atmosphere thousands of years from now.” Pieter Tans, lead scientist of NOAA’s Global Greenhouse Gas Reference Network.

With Kilauea volcano erupting continually for so long, many ask if that has a significant impact on atmospheric carbon dioxide. Researchers say it's clear that most of the CO2 change is from fossil fuel use, not the volcano.

And the proximity of Kilauea to Mauna Loa is also not a big factor. The high rate of growth in atmospheric CO2 is not only being observed at Mauna Loa but also at other sites in NOAA’s Global Greenhouse Gas Reference Network.

© Jan TenBruggencate 2018

Thursday, June 7, 2018

Rats can open a window on ancient island environments


It may be hard to think of something rats are good for, but a team of scientists has figured out a unique way to look into the history of Pacific islands—using rats.
(Image: A Pacific rat, Rattus exulans, in a New Zealand government photo.)

They looked into the bones of rats from ancient archaeological sites, and it turned out that they could extract information from the marrow of rat bones. They were able to figure out what the rats were eating over time, and from that, make assessments about the changing island environment.

A new study on this work was just published in the Proceedings of the National Academy of Sciences. The authors are Jillian Swift, Patrick Roberts and Nicole Boivin of the Max Planck Institute for the Science of Human History, and Patrick Kirch of the Univeristy of California-Berkeley Department of Anthropology. The paper is entitled "Restructuring of nutrient flows in island ecosystems following human colonization evidenced by isotopic analysis of commensal rats."

Some definitions: Isotopes are forms of the same element that have different numbers of neutrons in the nuclei. Isotopic analysis in this instance is studying changes over time in the mix of isotopes of certain elements—in this case carbon and nitrogen. And commensal means living with something, without causing it any particular help or harm—in this case rats living among humans.

When early Polynesians arrived on Pacific islands, they almost always brought Pacific rats with them. People argue over whether that was intentional or not, but it almost always happened. Pacific rats, or Polynesian rats, are Rattus exulans.

And those rats quickly went out on their own, foraging initially in the virgin environment, and later in the environment that humans had created through bringing new plants, slash and burn agriculture and so forth.

"Stable isotope analysis of commensal animals provides an effective proxy for local human environments because these species are closely associated with human activities without being under direct human management," the authors write.

They studied rat bones from archaeological sites in three Polynesian island areas: Mangareva, Ua Huka in the Marquesas and Tikopia far to the west.

They found that their study of rats was able to track dramatic changes in local environments, demonstrating "human land use, intensification and faunal community restructuring."

More specifically, "Our results highlight the large-scale restructuring of nutrient flows in island ecosystems that resulted from human colonization and ecosystem engineering activities on Pacific islands."

This is complicated stuff, and I won't go into details on how the lab work was done, but you can look it up yourself here.

This is data that the authors say is hard to get from standard analysis of early archaeological remains, and it suggests that this kind of stable isotope analysis can help shed more light on how and how quickly humans changed their environments after arriving on Pacific islands.

It is also true that the rats themselves did a lot of that modification of ecosystems—eating birds and insect and seeds and seedlings. But that's all part of the story, since it was humans who brought the rats to these new environments.

© Jan TenBruggencate 2018

Sunday, May 13, 2018

Dying `Ōhi`a: Lots of research, perhaps some hope







Dead `ohi`a with live trees and uluhe.
Credit: DLNR
Lots of news organizations spread word that a variant of the Rapid `Ōhi`a Death fungus has been found on Kaua`i, but none told the larger story.

That story is the powerful effort that’s going on to save the tree that has been called the mother of the forest.

`Ōhi`a is really a remarkable part of the Hawaiian environment, growing in many environments from sea level to high mountains, and in many cases serving as the dominant canopy tree.

It feeds and houses insects. Those insects and the tree’s nectar feed birds. And it houses birds, both in its branches and in cavities in its trunk.

It is prominent in culture, common in legend, and it’s just plain gorgeous with its crimson and orange puffball flowers and widely varying leaf types. Buds can be reddish or orange or green, and shiny or covered with a frost of silver hairs.

“It is the foundation tree of our watershed,” said Bob Masuda, deputy director of the state Department of Land and Natural Resources.

As a community we despaired when there arrived a fungus, Ceratocystis lukuohia, which began killing trees by the thousands on Hawai`i Island. Many trees were infected and once infected, death was certain often in days to weeks. It was sometimes called `Ōhi`a Wilt, and sometimes more dramatically, Rapid `Ōhi`a Death.

It turns out that a small percentage of trees was also infected with a slower-developing related fungus, Ceratocystis huliohia. It could take months to years to kill a tree, often taking single branch systems before killing off the entire tree. 

That’s the one that has now been found on East Kaua`i. Not nearly as virulent as its spooky cousin, but still a problem for `ōhi`a. Foresters suggest it probably shouldn’t be called Rapid `Ōhi`a Death, because, well, it doesn’t progress so rapidly.

Both are examples of something called a vascular wilt—a fungus that clogs the tree’s ability to transfer water between roots and leaves


There are some interesting things about these diseases, including that they appear to have very different sources. The fast-acting one is most closely related to fungi in Latin America, while the slower one appears to be more closely related to Asian fungi.

And the slower-moving version may spread slowly enough that it was in the Hawaiian Islands first, but wasn’t recognized. There are lots of things that can kill `ōhi`a trees, lots of disease that can attack them—although none as aggressive as Ceratocystis lukuohia.

One of the big unanswered questions about both diseases is whether there is hope. Whether there are any examples of `ōhi`a trees that may be resistant—and thus could be used to repopulate the Hawaiian forest.

To help find that out, lots of research is underway, including aerial surveys on several islands to better understand the outbreak. Here’s one study on the aerial monitoring from the journal Remote Sensing

Pathologist Lisa Keith, of the USDA Pacific Basin Agricultural Research Service, said that researchers are growing seedlings of different varieties of `ōhi`a and infecting them with the fungus. So far, some are still surviving—perhaps a good sign, although they may just be heading downhill slower than others.

She and others are also working with different fungicides, which may not save an infected tree, but might keep a particularly valued tree alive longer. Others are working with other techniques to try to strengthen the trees so they can potentially survive infection.

It’s clear that humans are big carriers. If a tool like an ax, chain saw or machete cuts an infected tree, it can easily spread the disease if you cut into a second tree without disinfecting the tool. Any injury to the tree can be a highway for infection.

Scientists are studying the beetles that may be spreading the disease by boring into the trees.

And they’re trying to determine how effective the fungus is at being spread by wind.

And what if it’s not just those beetles, but other insects. Researchers have chunks of infected tree wood in netted containers, to watch what other insects might emerge over time.

If the disease is spread by wind, then perhaps you could limit the spread by cutting down a swath of trees downwind from an infected patch, to deny the fungus trees to spread to. Kind of like cutting a firebreak.  The state Division of Forestry and Wildlife is working on that technique.

Researchers are studying old photographs of the forest to try to determine what they can about disease in `ōhi`a over the years.

And scientists have developed quarantine measures to reduce the spread—like limiting the movement of infected wood.

The number of organizations working on this issue is impressive. It includes the University of Hawaiʻi at Mānoa College of Tropical Agriculture and Human Resources, the U.S. Pacific Basin Agricultural Research Center, USDA Forest Service Institute of Pacific Islands Forestry, the Department of Land and Natural Resources’ Division of Forestry and Wildlife, University of Hawaiʻi at Hilo, The Nature Conservancy, National Tropical Botanical Garden, Hawaiʻi Association of Watershed Partnerships, Coordinating Group on Alien Pest Species, the Big Island, Maui, Molokai, O'ahu and Kaua'i Invasive Species Committees, USFS Region 5 State and Private Forestry, USGS Pacific Island Ecosystems Research Center, Carnegie Airborne Observatory,  Hawai'i Invasive Species Council and Hawai`i Department of Agriculture -Plant Quarantine Branch.


A sign of hope is that not every tree in a diseased stand dies. But it’s not yet clear whether that’s because surviving trees might be resistant to the disease, or that they simply haven’t been infected yet.

That said, the `ōhi`a is so important to the Hawaiian environment that researchers and foresters hope to be able to identify resistant trees.

If they can find them, then the daunting task will be a massive statewide effort to replant these seminal trees throughout the Hawaiian forest.

© Jan TenBruggencate 2018


Friday, March 23, 2018

Vampire Mice II: Mice changing diet, growing bigger as they attack giant seabirds


 Laysan albatross with mouse injury. Credit: USFWS.
Like characters in some horror movie, house mice are moving up the food chain and getting bigger.

They’re feeding on chicks and now adult seabirds, leaving hundreds of three-foot-tall albatrosses bleeding from their necks, heads and backs, like victims in a vampire flick.


In one case, they are also changing in size—nearly doubling in mass on one Atlantic island where they aggressively eat seabird chicks.
The lowly mouse, Mus musculus, has always been an omnivore, but they’ve never had the reputation of rats as attack rodents. That is changing on islands around the world.

The latest spooky change in their level of aggression came on  a remote Hawaiian Island: Sand Island at Midway Atoll at the remote western end of the Papahānaumokuākea Marine National Monument, which takes up all of the Northwestern Hawaiian Islands and considerable square mileage of the surrounding waters.

On Midway, mice are biting the necks of adult Laysan albatross, chewing down skin and fat and muscle, and drinking blood.  Hundreds of the big birds have been found dead, and more hundreds of abandoned nests suggest other injured parent birds may have died at sea.

Night video of the nesting areas show the tiny gray mice climbing the backs and necks of the albatrosses, repeatedly sipping at gaping wounds they have chewed into the birds’ bodies.

Mice going after big adult birds at Midway started out of the blue in 2015, and this was new. This was another step, something not seen before anywhere. Wildlife officials are now studying ways to wipe out the mouse population, before the predation gets worse.

We wrote about this at Raising Islands here

Efforts to control predation on important seabird nesting islands has previously mainly focused on rats—mainly Pacific rats and black rats, which are also known as roof rats and ship rats. But in the past two decades, mice have stepped up as serious predators of seabirds.

Mice have been caught attacking soft chicks and eggs on bird nesting islands for some time. Here is a Live Science piece on attacks at other islands. 

On Gough Island in the South Atlantic, game cameras recorded swarms of mice attacking nestlings of Tristan albatross (Diomedia dabbenena,) great puffins (Puffinus gravis) and Atlantic petrel (Pterodoma incerta.)

“One video showed up to 10 mice mauling an albatross chick and eating from three open wounds on its body,” wrote Live Science writer Jeanna Byer in 2007.
Puffins and petrels are smaller seabirds, the size of mynah birds or pigeons. Albatrosses, which can be three feet tall with wingspans of six to 11 feet, are huge.  A mouse standing up might reach four inches in height. In climbing an albatross, they are climbing a bird nine times taller than they are.
The authors of a 2012 scientific paper in Animal Conservation on that situation wrote: “mice cannot be ignored as a potential threat to island fauna, and island restoration and management plans should routinely include eradication of introduced mice.” 

Injured albatross at Midway in colony. Credit; USFWS.
A 2016 piece in Smithsonian suggests that mice, fed on a rich diet of seabird flesh, are actually changing in size—getting huge. 

They are nearly twice the weight of standard house mice. The standard house mouse is tiny, weighing only about 16 to 25 grams. On Gough, the average mouse runs more than 35 grams.

“They’re the largest and heaviest mice anywhere in the world,” said Richard Cuthbert of the Wildlife Conservation Society.

Cuthbert was the lead author of a 2016  Journal of Mammalogy  article that suggested that the bird diet is a primary cause of the change in mouse size. 

Of course it is not only adult birds that mice attack when they get established on islands. 

Wildlife officials in New Zealand have noted mice killing not only seabird chicks but native lizards, seedlings and bird eggs. New Zealand has removed rats and mice from several offshore islands.

© Jan TenBruggencate 2018

Thursday, March 22, 2018

Vampire mice killing hundreds of Laysan albatross on Hawaiian island of Midway


Bloodied albatross. USFWS photo.
The mysterious vampire mice of Midway Atoll have left hundreds of adult Laysan albatross dead, their necks torn open in garish bloody wounds.

These mice are doing something no mice anywhere else in the world are known to do.

Late at night, they climb the necks of nesting seabirds and chew through the skin, apparently feeding on the birds’ blood, skin, fat and muscle.
The albatross’ commitment to protecting their eggs is so strong that they will shake their heads, but will not leave the nests even with a predatory rodent chewing on them.

And the problem has grown since it was first spotted in 2015.

Wildlife officials assess injured Laysan albatross. Credit: USFWS
“It is horribly destructive what they do to those birds,” said Matt Brown, the U.S. Fish and Wildlife Service superintendent for the Papahānaumokuākea Marine National Monument, which includes Midway.

The Fish and Wildlife Service has teamed up with a number of agencies and now hopes to eradicate the mice, which are an alien species to Midway. Among the 10 major atolls, reefs and islets of the Northwestern Hawaiian Islands, mice only occur on Sand Island, one of the three specks of dry land within Midway Atoll.

The mice have been here at least since World War II, but the new vampirish behavior is both new to Midway and apparently new to science. Mice are known to take eggs and nestlings of seabirds elsewhere, but only on Midway do they attack large adult birds.

“This isn’t a behavior that has been observed before, although rodents have been responsible for a number of seabird extinctions and extirpations on islands,” said Megan Nagel, public affairs officer for the Fish and Wildlife Service in Honolulu.
A Fish and Wildlife Service fact sheet quoted Midway Atoll Refuge manager Bob Peyton: “The Service is working against the clock to determine how many birds have been attacked, what the rate of spread is, and how to stop the attacks. Albatrosses lay only one egg a season.” 

The proposal they’ve come up with is to try to eradicate the mice. New Zealand just completed a successful five-year effort to remove mice from the Antipodes Islands, where they were feeding on chicks and eggs of seabirds, apparently including the Wandering Albatross, whose 10 to 11-foot wingspan makes it one of the biggest of birds. 

The Midway approach will be similar to the one used at the Antipodes: a helicopter drop of toxic bait pellets during a period when the nesting seabird population is at its lowest.  That’s also similar to the technique that has been used to remove mice from more than 80 other islands and to remove rats from more than 400 islands around the world.

In Hawai`i it’s much like the system that was used to eradicate Pacific rats from Mokapu Island off Molokai and black rats from Mokoli`i off O`ahu, and which has been used to control rats at Lehua Island off Ni`ihau, a process that is still underway.
Rats were eradicated from Midway’s three islets in 1996.

The environmental assessment for the Midway mouse effort, under the name Midway Seabird Protection Project, describes the issues and the proposed solution. The public comment for the environmental assessment is open through April 20.

The helicopter would achieve a uniform islandwide distribution of specially designed bait pellets that contain the anticoagulant Brodifacoum. Some hand distribution will be employed in sensitive areas such as near the shore. The work would be done in the summer of 2019, during a period when seabirds are comparatively scarce on the island, and when dry weather limits mouse food supplies—making the grain-based bait pellets more appealing.

There are a number of reasons to use a helicopter, including assuring an even bait distribution but also foot traffic in many areas would collapse many of the thousands of nesting burrows of Bonin Petrels, which recovered strongly after rats were removed.

Similar eradication efforts on other islands have usually but not always been successful. In recent years, the success rate has gone up with improvements in technique. The environmental assessment reviews alternative approaches, and looks at the option of doing nothing at all.  The Brodifacoum bait delivered by helicopter at the right time of year, in specific amounts over time, as described in the proposal, is viewed as the best alternative.

The project is estimated to cost $3.5 million. It is not yet clear the source of that money. Many previous eradications have been funded through a combination of government funds, grants from foundations, and money from private institutions like conservation groups.

The Fish and Wildlife Service would be the lead operational agency, with technical support and assistance from Island Conservation and the Midway Restoration Partnership Group. This is a collaboration of the Fish and Wildlife Serfvice and Island Conservation as well as American Bird Conservancy, the National Wildlife Research Center of the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, National Oceanographic and Atmospheric Agency, U.S Geological Survey and the state Office of Hawaiian Affairs.

© Jan TenBruggencate 2018
What's at risk :Midway albatross colony. Credit: USFWS.

Saturday, March 17, 2018

Massive pesticide testing confirms: Hawai`i Surface Waters "Meet State & Federal Water Quality Standards"


Ground zero has somehow slipped away. There is no evidence of widespread pesticide contamination in Hawai`i’s surface waters, according to a thorough federal study of water resources on two islands.
That confirms similar results in separate tests from 2014 and 2016.

It would seem that HAPA, SHAKA, the Center or Food Safety can fold up their tents and go home. Their work is done. If the claims of rampant agricultural pesticide misuse were ever true, they are not true now.

The U.S. Geological Survey conducted 7,200 water tests in 2016 and 2017—one of the broadest scientific investigations ever into allegations of pesticide misuse in the Hawaiian Islands. There were 12 surface water test sites on Kaua`i and 19 on O`ahu.

Here is the state Department of Agriculture public release on USGS testing of water samples at 31 sites on Oahu and Kaua`i, for 225 different pesticides. 

“The sites included streams, ditches, canals, and a wetland– and were near or downstream of agricultural areas, developed areas, or both,” the study said.  Here is the study itself

The short version: The laboratory tests were able to detect pesticides, but all at levels below federally and state levels of concern.

Bizarrely, while the last decade of allegations of pesticide misuse have gained widespread publicity across the state, the proof that those claims were unfounded has slipped almost entirely under the radar.  

The state’s news media allocated pages upon pages of newsprint and web content to pesticide contamination allegations, but almost nothing to the actual scientific proof that these claims were were overblown.
The Garden Island newspaper on Kaua`i, dismissed the study in a brief (9 paragraph) story.  Honolulu-based media have had nothing to date. 

The new USGS study is now being repeated on O`ahu and Kaua`i, and is also being expanded to Maui and Hawai`i counties.

“This multi-year surface water study goes a long way towards assuring the citizenry of Hawaii that pesticides are continuing to be used properly,” said Scott Enright, chair of the Hawaii State Department of Agriculture.

The surface water study is not an outlier. It confirms the conclusions of several previous studies.

It supports information by a groundwater study by an independent California laboratory for the Kaua`i Department of Water Supply in 2016, which found no pesticide levels of concern in groundwater from several Kaua`i agricultural sites. Here is the RaisingIslands coverage of that study. 

That study confirms annual testing by the island’s Water Department of all its drinking water sources. Those tests can be seen here

A statewide surface water testing effort in 2014 had results along the same lines. Here is Honolulu Civil Beat’s piece on that statewide program, which found that most pesticide concerns were in urban streams, and not in agricultural areas. 

As noted above, the new USGS study did not fail to find pesticides, but where it found them they were at exceedingly low levels. Here are some of the notable findings, from the state Department of Agriculture release, including what is being done about those pesticides:

“Chlorpyrifos was detected in two Honouliuli stream samples collected during the same high-flow storm event. The highest concentration of 23.3 ng/l is below the state water quality standard of 83 ng/l and the strictest acute benchmark of 50 ng/l for the protection of freshwater invertebrates. HDOA is currently in the process of restricting the use of chlorpyrifos by reclassifying it to a restricted-use pesticide (RUP) which will allow its use by only state-certified applicators. The proposed restrictions will mirror what California has done and includes required buffer zone. These rules are anticipated to be finalized by this summer.

“Concentrations of flubendiamide in high-flow samples collected at two sites on Oahu exceeded the lowest Federal aquatic-life benchmark. Flubendiamide is an insecticide that the U.S. Environmental Protection Agency (EPA) is currently in the process of cancelling its use due to the risk to aquatic invertebrates and aquatic environments.

“Atrazine, an herbicide and established groundwater contaminant, and an RUP was detected in low-flow samples at three sites, at concentrations more than 100 times lower than the EPA maximum contaminant level for drinking water and the strictest aquatic life benchmarks. This represents a significant drop compared to the 75 percent detection rate in a 2013-14 study. The decline likely reflects the decrease in current atrazine applications and sales statewide after 2015, during the time that saw the closure of a large sugarcane plantation.

“Bromacil is an herbicide and established groundwater contaminant used almost exclusively on pineapple in Hawaii. Bromocil was detected in two areas, one of which is known to have grown pineapple.”

All but one of the samples identified at least one pesticide compound. A total of 61 different pesticides were identified across the two islands. The most commonly identified pesticide was Atrazine—either directly or from a compound that Atrazine degrades into.

Atrazine is a long-lived herbicide that was commonly used in the sugar industry, but is still used to control broadleaf weeds in agriculture today. It is the agricultural chemical most widely detected in water samples across the nation.

© Jan TenBruggencate 2018