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There is a saying that March comes in like a lion and goes out like a lamb. This year March saved the lion part for the middle of the month. Over the weekend, we had a major winter storm with heavy wind and about four inches of rain in 48 hours (some places got more than that). As result the river flooded any low-lying areas, such as my local park.
  Someone flooded the bathrooms.  Of course, the local Canada Geese took full advantage of the expanded waters.   For the sake of comparison, the view from the top of the hill should look something like this (in summer). The benches in the top photo are these ones. Some towns fared far worse; in Bound Brook, where the river crested at 31.45 feet, the police had to patrol the streets on jetskis and rubber dinghys to evacuate residents. In Highland Park, the water only reached about 15 feet, which is not sufficient to flood the town. Even so, this was the highest I have seen the river in a long time. Newspaper accounts compared it to the aftermath of Hurricane Floyd. Last week, the Interior Department, Audubon, and a coalition of other conservation-minded organizations announced the 2010 State of the Birds report. (Oddly, the report was released late on a Thursday; usually the end of the week is reserved for news that agencies would prefer people not notice, like bank failures.) This year's report tries to predict how birds might respond to climate change. It suggests conservation actions to mitigate those responses and reduce stress as the climate continues to warm.
 Relative vulnerability of U.S. birds by habitat The report divides birds into groups based on broad habitat types or location. Since this was produced in part by the Interior Department, the report includes all birds found in the United States and its territories, including islands in the Pacific and West Indies. Each bird species was assessed on five traits and rated as high, medium, or low vulnerability based on that assessment. Here, briefly are some of the report's predictions.
 Mitigation is going to become increasingly important as the climate continues to warm. At this point it seems unlikely that we will see effective action from the U.S. Congress on climate change. Even if the EPA is successful in imposing greenhouse gas restrictions, its restrictions may not reduce emissions quickly enough. So we are likely looking at some pretty dramatic changes over the next few decades, and long-term conservation plans will need to account for that.  Piping Plover at Little Talbot Island / Photo by Pat Leary One of the color-marked Piping Plovers from Andros Island in the Bahamas has been resighted. The bird pictured above was captured and banded on February 17 on Andros Island. Pat and Doris Leary found it while birding at Little Talbot Island in Duval County, Florida, on March 12. This bird was the last plover to be marked and the first to be resighted. From Andros Island to Little Talbot Island is about 440 miles by air. I did not see any plovers while I was at Sandy Hook last weekend, but I will be watching for them when I am at coastal spots. For updates on the plover marking project (and other bird banding activity), follow the CVWO First Landing blog.  "We were really surprised to discover that ancient DNA is well-preserved in fossil eggshells, particularly the heaviest bird to have existed the elephant bird called Aepyornis, which is now extinct," said Murdoch doctoral student Charlotte Oskam, who undertook the research.The research team hopes to use the same methods for ancient moa eggshells to study how humans and moas interacted. Extracting DNA from fossil remains could probably clarify some taxonomic relationships as well. If you wish to read about this study in more detail, you can read the paper for free on the Royal Society's website.  Loggerhead Shrike / Photo by Dave Menke (USFWS) Birds and birding news
Last week, I expressed some frustration with the Obama's administration's record on endangered species after it placed Greater Sage-Grouse on the list of candidates. Up to that point, only two species had been listed under the Endangered Species Act since Obama took office, while 249 species have been sitting on the candidate list. This week that changed in a big way, with two announcements.
 Loggerhead Sea Turtle at Archie Carr NWR / Photo by Ryan Hagerty (USFWS) First, the National Marine Fisheries Service and U.S. Fish and Wildlife Service issued a joint proposal to list the Loggerhead Sea Turtle (Caretta caretta) under the Endangered Species Act. Loggerhead Sea Turtle has nine distinct populations around the world. Of these, two will be designated as threatened and seven as endangered. The two populations that occur in U.S. waters, the North Pacific and Northwest Atlantic populations, will both be designated as endangered. Loggerhead Sea Turtles worldwide are currently classified as threatened; the new listing is in response to petitions regarding the two U.S. populations. This is a proposed rather than final rule, so it will undergo a public comment period first. If you wish to comment on the proposed listing, you can do so at www.regulations.gov until June 14, 2010. Once the Loggerhead is listed as endangered, the government will be required to designate critical habitat to protect feeding areas in the ocean and nesting areas on beaches.  ‘Akeke‘e (Loxops caeruleirostris) / Painting by John Gerrard Keulemans Second, 48 endemic species from the Hawaiian island of Kaua'i were listed as a group since they share habitats and have similar threats. This action addresses some of the backlog in listing petitions. An ecosystem approach is particularly suitable for Hawaii since so many vulnerable species occur in a relatively small area. It provides a way for the government to protect entire ecosystems rather than the narrow ranges where a species is known to be found. The USFWS plans to list new species by ecosystem on other islands in the next few years. The 48 newly listed species (pdf) include 45 plants, 1 insect, and 2 birds. Among the 45 plants are several that have not been seen for several years, though they still exist in remote areas. One plant, Diellia manii, was considered extinct until its recent rediscovery. The insect is Drosophila sharpi, a Hawaiian picture-wing fly. The two birds are ‘Akeke‘e (Loxops caeruleirostris) and ‘Akikiki (Oreomystis bairdi). Both are Hawaiian honeycreepers and members of the finch family. They may be better known as Kaua'i 'Akepa and Kaua'i Creeper. These species had appeared stable until the mid-20th century, when both populations suffered precipitous declines. There are now about 3,500 'Akeke'e and 1,300 'Akikiki. Along with listing the 48 endangered species, the USFWS designated critical habitat for 47 of them. The critical habitat covers 26,582 acres in six ecosystem types, 98% of which overlaps the critical habitat already designated for other endangered or threatened species. Most is on state-owned lands. Critical habitat was not designated for one palm species because it is a prized plant for collections; the USFWS was concerned that designating critical habitat might alert collectors to its location. A couple weeks ago, I posted about the extraordinary number of suffering Brown Pelicans that have been washing up on California's beaches this winter. The state's wildlife agencies now have an answer: food supplies are low.
The California Department of Fish and Game (CDFG) is reporting that the primary causes of the recent Brown Pelican mass stranding (involving varying degrees of incapacitation of hundreds of birds) along the Oregon and California Coast are related to shortages of preferred prey items, such as anchovies and sardines, and rough winter weather likely related to the current El Niño event.The IBRRC is caring for 300 birds right now, but at least the number of new patients is decreasing. Sick pelicans have responded well to treatment (mainly washing and feeding), and the center has been releasing rehabilitated pelicans in batches. (As of February 19th, 200 pelicans had been released.) I do not see anything about the CDFG announcement yet, but the IBRRC blog is a good place to check for updates on the pelicans.  The problems were worse than I imagined. The state has since scaled back the deal, so that it will now purchase only 72,800 acres for $536 million. Meanwhile, U.S. Sugar will retain the rest, including its production facilities, and remain in operation for the foreseeable future. In fact, this deal may do more to revitalize U.S. Sugar than the Everglades. Negotiations favored United States Sugar from the start, when the state accepted two outside firms’ appraisals of the company’s land that used figures from the height of the real estate market, according to documents.Some elements of this case ought to be scandalous. Why were terms of the purchase so favorable to U.S. Sugar and why were key parties – like a rival company, federal agencies, and the Miccosukee Indian tribe – shut out from the process? Part of the reason is that U.S. Sugar has close ties to Charlie Crist: United States Sugar had an unusually powerful advocate in Gunster, a West Palm Beach law firm that had represented it since 1990. Gunster’s chairman, George LeMieux, was Governor Crist’s chief of staff when the deal was first conceived. Mr. LeMieux, who began working at the law firm in 1994, returned to it in January 2008 as the deal was being renegotiated.While LeMieux claims to have recused himself from the deal, his close ties with Crist would have given U.S. Sugar an inside edge on negotiations. Even if LeMieux did not talk to Crist about the deal, he did advise U.S. Sugar during the process. Another reason the terms were so favorable is that Crist's negotiators chose to accept the land appraisal most favorable to U.S. Sugar, even though other independent appraisers and the state's own environmental agency thought that the land was overvalued, even at the time. Since then the land's market value has declined due to the crash in the real estate market. According to some estimates, the state agreed to pay $7,000 an acre for land that is now worth $4,000 per acre. Much of the remaining land in the deal is heavily contaminated with copper, DDT, selenium, and arsenic. Cleaning up that mess will cost even more. Some areas to be purchased by the state, such as the company's citrus groves, are too elevated and dry to be suitable for wetlands restoration. This would be just another corrupt land deal if it were for for its potential to set back restoration efforts in the Everglades. Already completion of a giant reservoir costing $800 million – a key piece in the system of canals and reservoirs to restore the natural flow – has been stalled indefinitely because of the purchase. The cancellation of construction contracts cost the state $25 million in fines, on top of the $282 million it had already spent on the project. Whether other projects will need to be canceled remains to be seen. The U.S. Sugar deal may still turn out to be worthwhile, but for now it is an obstacle to completing the original restoration plan.      At Sandy Hook we were greeted by a Red-winged Blackbird singing from a power line – the first of many on the peninsula. At the first stop alone there were four males singing for territory. Song Sparrows too were singing, and each male seemed to perform a different variation of the basic song. Other singers included multiple Northern Mockingbirds, a Northern Cardinal, and a Carolina Wren. With the exception of Black Ducks, waterfowl were relatively scarce. I am not sure if this is because the wintering birds have already moved north or because prolonged freezing temperatures earlier in the winter drove the usual winter flocks south. Small flocks of Black Scoters and Long-tailed Ducks dotted the ocean, along with a few Horned Grebes. On the bay side, there were Brant, Red-breasted Mergansers, and Bufflehead. I saw only one loon, a Red-throated Loon on the bay. Yellow-rumped Warblers were very active, calling in the bushes and flying overhead. A very large flock of Cedar Waxwings was circulating around the boy scout camp area. A Red-tailed Hawk was circling in the same area. I am not sure if this was a resident bird or a northbound migrant.   Greater Sage-Grouse / Photo by Dave Menke (USFWS) In its Friday news dump, the US Fish and Wildlife Service finally announced whether it would list the Greater Sage-Grouse under the Endangered Species Act. Salazar made the announcement in conjunction with a finding by the U.S. Fish and Wildlife Service that, based on accumulated scientific data and new peer-reviewed information and analysis, the greater sage-grouse warrants the protection of the Endangered Species Act but that listing the species at this time is precluded by the need to address higher priority species first. The greater sage-grouse will be placed on the candidate list for future action, meaning the species would not receive statutory protection under the ESA and states would continue to be responsible for managing the bird....The agency also announced that there was insufficient evidence to treat the Mono Basin population of Greater Sage-Grouse as a separate subspecies. As a result, it will be handled together with Greater Sage-Grouse in other areas for listing purposes. This population is found in California and Nevada. The decision leaves the Greater Sage-Grouse in the same administrative limbo as numerous other species, including the Red Knot. There are currently 249 candidate species for listing under the Endangered Species Act. In recent years, the candidate list seems to have become the most likely destination for endangered species petitions. It has some advantages as a designation in that the USFWS will coordinate voluntary conservation measures among federal agencies, nonprofit organizations, and private landowners. Its status will also be reviewed annually to monitor progress. The USFWS emphasizes these aspects in its press release. However, candidate species do not receive the full set of legal protections that endangered or threatened species receive. While the Greater Sage-Grouse will continue to receive protection from direct killings or nest destruction under the Migratory Bird Treaty Act, it will not benefit from the Endangered Species Act's habitat protections. The USFWS will also not be legally compelled create and implement a recovery plan, which leaves conservation measures subject to the goodwill of whatever administration is in office. Speaking of administrations, the Center for Biological Diversity pointed out that the Obama administration has listed only two species under the Endangered Species Act so far. This is lower than the Bush administration's annual average of 8 species listed. Both administrations have shown a marked departure from endangered species policy under the previous two administrations, which listed annual averages of 65 and 58, respectively. While the current administration has made some initial progress in rolling back the worst attacks on the Endangered Species Act, it needs to do a better job of extending the law's protections to the species that need it.  Northern Pintails / Photo by Wyman Meinzer (USFWS) Birds and birding news
 When I lived in Washington, I always took the train if I wanted to visit New Jersey. Because Amtrak makes very few stops in central New Jersey, I usually changed trains in Trenton, switching to New Jersey Transit, the state's commuter line. I forget exactly when I became aware of it, but at some point I realized that the station is home to a very large crow roost: during the day the trees along the tracks will be mostly empty, but at night they will be filled with crows. When I say "large," I mean a roost for over a thousand crows, lining the train station on either side. The last time that I passed through Trenton at night, the crows were there as usual.
Crows are nearly ubiquitous. I tend not to notice them much in my current neighborhood; I never see more than a handful at a time, and only occasionally around my house. In most other neighborhoods where I have lived, crows were much more in evidence. At one apartment, crows would sit on another wing of the building almost every day and caw at each other for reasons that I was unable to discern at the time. On some of my walks at Kenilworth Aquatic Gardens, I encountered such a noisy group of crows that it was difficult to hear any other birds.  Crow Planet is part natural history and part memoir. Haupt's observations form the core of the narrative. A family of American Crows nested near Haupt's home, and she watched and recorded their behavior regularly as they built their nest, raised young, foraged, and warded off predators. One of their fledglings broke its leg after leaving the nest, and somehow it survived to adulthood with the assistance of its parents. In addition to that family group, she watched crows at every opportunity around Seattle to discover how they interact with the urban landscape. Haupt reports the behaviors she observed without overly anthropomorphizing them, even as she tries to interpret what the behaviors mean. To an inexperienced observer, crow vocalizations may all sound alike – a simple caw caw caw. After watching and listening to crows for some time, Haupt was able to recognize several different call types, such as assembly calls, contact calls, scolding calls, and nocturnal roosting calls. She interweaves her own observations with scientific research on crows so that the book stays firmly grounded. In the case of crow vocalizations, scientists have identified 23 types of calls, each with a subtle but distinct usage. The observed behaviors of crows become a starting point for exploring how a naturalist and environmentalist can be at home in an urban space. This is a particularly personal question for Haupt since she ended up moving to Seattle more by necessity than by choice. Crow Planet is party about how she came to terms with living in an urban neighborhood instead of the farm she had imagined. Cities offer certain advantages for an environmentalist: walkable neighborhoods and public transit make driving largely unnecessary, and a conscientious consumer has more choice of organic food or fair trade products. However, living in a city curtails one's experience of the natural world. Relatively few animal species can survive in the densest urban spaces; even in less dense neighborhoods, biodiversity is relatively low. This means that an urban naturalist needs to look more carefully at what species are present in whatever fragments of habitat remain. Crow Planet provides one model for doing that.  'I'iwi / Photo by Kaleomokuokanalu This week the US Fish and Wildlife Service published its first revision of the List of Migratory Birds that are protected under the Migratory Bird Treaty Act (MBTA) since 1985. The MBTA protects birds that occur in the United States and its territories, especially bird species that are not covered by the Endangered Species Act. It bans the "taking" of wild birds – which includes killing, capturing, injuring, or possessing bird parts or nests – without a federal permit. While enforcement is uneven, it provides a tool for addressing some of the most egregious bird killings. Since this was the first revision in 25 years, there were a lot of changes to make. The USFWS added 186 species to the list and subtracted 11, so that the list now includes 1007 bird species. The final rule published in the Federal Register contains the complete list of changes (pdf). Some changes are very basic. The USFWS relies on lists published by the American Ornithologists Union's checklist of North American birds and Monroe and Sibley's checklist of world birds. The AOU has made numerous changes to bird taxonomy and nomenclature since 1985; these changes needed to be reflected in the federal list. The common or scientific names of 114 species were changed to conform with current practices, while 38 species were added to the list due to taxonomic splits. Meanwhile, one taxon, Black-backed Wagtail, was removed because it is now considered a subspecies of White Wagtail. It also corrects some misspellings. Past versions of the List of Migratory Birds excluded species viewed as accidental or casual within the United States. The USFWS has since changed its views regarding such rare birds and now views protection of these species to be consistent with the MBTA's purposes. The current revision thus adds 94 species whose normal range occurs outside of the United States but that have accepted records within the country. This group includes such species as Common Chaffinch, Red-footed Falcon, and Western Reef-Heron. Ten species were removed due to lack of evidence that they occurred naturally within the United States. Muscovy Duck, native to South and Central America, was added to the list because its range has been expanding northward. A small wild population now occurs naturally in Texas. However, most of the Muscovy Duck populations in the United States are the result of human introductions and in some cases they are bred for food production. A separate rule (pdf) addresses some of the issues regarding this species. The headline change, announced in its own press release, is that the new List of Migratory Birds includes more birds from Pacific islands. The new list adds 24 Hawaiian endemics, such birds as Akikiki, 'I'iwi, and Hawaii Creeper. It also adds 28 species that occur on other US territories, such as American Samoa and the Northern Mariana Islands. The latter group includes such species as Mariana Crow and Micronesian Kingfisher. I am not sure why the Hawaiian species were not covered by previous versions of the list, but at least the omission has been rectified. One addition that the USFWS chose not to make is Cackling Goose. In 2004, the AOU split the 11 subspecies of Canada Goose into two groups; 7 remained as Canada Goose while four became Cackling Goose. The USFWS regards the genetic basis for the split to be inconclusive since some analyses of nuclear DNA show evidence of hybridization. It requests further evidence before making any change to these 11 subspecies. In the case of Canada and Cackling Goose, changing the list would require changing hunting regulations and educating the public about identifying the new species, so the agency wishes to proceed more cautiously.  I recently found some historical images of the C&O Canal from DCPL's Thompson collection. Most of them are undated, but they appear to show the canal during its last decade or so of operation. Click through the images to go to the photo pages on Flickr.      One evening last spring, Chris Cunningham was sitting on his patio enjoying a cocktail and observing the state bird of Georgia, the brown thrasher. It was out in the yard doing whatever it is that thrashers do when Cunningham was seized by a thought.His campaign includes a video that praises chickens and describes the Brown Thrasher as "inedible, lazy and migratory." It is hard to tell how serious this is or how likely the campaign is succeed in its stated goals. To me it seems that its real goal may be generating publicity for his restaurant chain or perhaps for some future venture. If Georgia did make the proposed switch, it would join Delaware and Rhode Island in using the domestic chicken as its state bird. Those two states each chose domestic chicken breeds that are connected with the state, Delaware's Blue Hen and the Rhode Island Red. It is not clear whether this proposal involves a breed specific to Georgia. The only chicken named on the campaign website is "Cornish chicken," which appears to be a common meat industry breed. The fact that a Georgian breed has not been named is one factor that makes me suspect that the proposal is not very serious or likely to get far. Whether the campaign is serious or not, it is not necessary to defame Brown Thrashers in the process. A migratory bird could hardly be described as lazy, as migratory birds expend much energy and undertake great risk to make their journeys. The Brown Thrasher is a short distance migrant, and in fact overwinters in most of the southern states, including Georgia. Even so, the cycle of moving between breeding and winter grounds and caring for young makes for a very demanding lifestyle. The assertion that Brown Thrashers have not done anything for Georgia is also not true. For one, the Brown Thrasher lent its name to Atlanta's professional hockey team. (Would they become the Atlanta Chickens?) More broadly, they contribute to the proper functioning of Georgia's ecosystems. As omnivores, they eat a variety of insects and other invertebrates, some of which could be harmful to the state's agricultural industry. Healthy and diverse ecosystems contribute a variety of other economic services, such as cleaning pollutants from air and water. While the Brown Thrasher alone is unlikely to attract many visitors, thriving and diverse bird life can attract ecotourism. In the end, this is not my state, so I am looking at this entirely as an outsider. However, I would be saddened to see such an extraordinary singer and feisty wild bird dropped as a state bird in favor of a domesticated one. (Thanks to Nick for sending me the link.) Update: Georgia Conservancy has a petition to keep the Brown Thrasher as state bird.  The Audubon Magazine blog has a summary of the early results. Some of the unusual reports included Yellow-billed Loon, Yellow-billed Cuckoo, Rustic Bunting, and Rufous-capped Warbler. You can see what else was reported on the GBBC's "explore the results" page. Among the things you can see on that results page are the species reported in each state and locality. The lists are sortable, so it is easy to see which birds have been reported the most at a variety of geographic levels. You can also see data presented in map form and view reports for individual species. Below are two tables of species reported in New Jersey. The first shows the species that were reported in the greatest numbers.
The second shows the species reported on the most checklists.
There is nothing surprising on New Jersey's top ten lists. Birds like Snow Goose and Canada Goose gather in large flocks, so they appear in large numbers on relatively few checklists. Downy Woodpecker and Tufted Titmouse range widely, so they show up on many checklists, but birders usually only see one or two at a time, so they appear in the GBBC results in smaller numbers than other common birds. One question going into this year's GBBC was how much the Pine Siskin count would differ from last year. In 2009, the GBBC recorded 7,848 Pine Siskins on 664 checklists in New Jersey. This year, New Jersey birders reported 185 siskins on 52 checklists. The difference is remarkable and emphasizes just how extraordinary last year's irruption was.  Color-marked Piping Plover / Photo by Ann Maddock Within the next few weeks, Piping Plovers will start arriving in the Mid-Atlantic states, either to stay and breed or to rest briefly en route to breeding grounds farther north. (Last year, I saw my first of the year on March 14 in New York.) This year, some of the plovers may be marked with colored leg bands as part of a migration study. A Piping Plover with a black flag near the top of its left leg, like the one above, is likely to be part of a population that winters in the Bahamas. How may a sighting be reported? Simple. Report all sightings to CHERI GRATTO-TREVOR, Prairie and Northern Wildlife Research Centre, Environment Canada, 115 Perimeter Road, Saskatoon, SK S7N 0X4 Canada, EM: cheri.gratto-trevor@ec.gc.ca , noting the color and location of each band on the bird, and location and behaviour of the bird (on nest, brooding, foraging at migratory stop-over, etc.), as well as presumed sex of the bird, if possible.So far only the only previously banded Piping Plover to be resighted belonged to the Great Lakes population. That bird, an adult female, was banded in 2005 on her breeding grounds in Michigan. She has returned to Michigan to nest each year since then but was not recorded elsewhere until she was seen in the Bahamas. Of the 57 color-marked Piping Plovers that are part of the current study, 50 were observed again within 24 hours of being banded. Many were seen during subsequent weeks, but they will be leaving the Bahamas very soon. These birds could be part of the Great Lakes population, or they could migrate and breed elsewhere. If you notice any Piping Plovers with color bands this year, make sure to record the colors and positions of all the bands and report the sighting. The Piping Plover is federally listed as endangered in the Great Lakes region and threatened in the Northern Great Plains and Atlantic Coast. While their status has been improving thanks to the recovery program, the species is still vulnerable. More information about where each of the populations migrates and breeds will assist recovery efforts. More details on the project and how to report sightings, along with additional photos of banded plovers, are available at the Coastal Virginia Wildlife Observatory blog.  Winter Wren / Photo by Shanthanu Bhardwaj Birds and birding news
A pair of Red-tailed Hawks appear ready to return to their nest at the Franklin Institute in Philadelphia.
Their webcam is officially up and running. Last year, it gave thousands of viewers a peek-a-boo view of a red-tailed-hawk couple nesting on a ledge of the Franklin Institute. They hatched three young that flapped their way into the hearts of fans worldwide.It helps the birds' popularity that their nest is in such a prominent location. The average Red-tailed Hawk nest is more concealed than a window ledge in the downtown of a major city. The best way to follow the breeding season's progress is at the Hawkwatch blog and, of course, the nest webcam. It is wonderful that we have the opportunity for such an intimate view of nesting activities while causing minimal disturbance. A wind farm has been proposed for a site within Puerto Rico's Karso del Sur Important Bird Area.
I support wind energy when thorough environmental reviews are completed and turbines are sited and operated in ways that cause the least amount of damage to birds and other wildlife. This project is an example of exactly what not to do. Wind farms can harm wildlife in two ways. One way involves bird collisions with the blades or turbine towers; this is probably the best known danger. In addition, bats may be harmed by changes in pressure around the blades. The second way wind farms harm wildlife is through the destruction and degradation of their habitats. Land needs to be cleared for the turbine site and for roads to transport construction material to the site. What wildlife habitat then remains around the site will be more vulnerable to invasive species and less able to support species that specialize in the habitat that was cleared. Clearing land and building an industrial wind farm in an Important Bird Area should be out of the question, especially in an area with so many sensitive and restricted-range species. Putting turbines in a bird-rich area like an IBA is likely to result in too many collisions, some of which will be critically endangered birds like the Puerto Rican Nightjar. Many of the species that inhabit the IBA are classified as critically endangered or endangered precisely because their range is so small. Any further range reductions that occur because of destroyed habitat will hasten the species' slide towards extinction. For those reasons, building a wind farm at sites like this will not be appropriate. I am glad to see that the Planning Board of Puerto Rico has blocked the site permit.  Common Raven / USFWS Photo Corvids – crows, ravens, jays, and magpies – are well known to be among the most intelligent of birds. Along with parrots, corvids have been a frequent subject of avian intelligence studies. Experiments have documented problem-solving and tool use, both in the lab and in the wild. Many of the recent experiments have tested intelligence in New Caledonian Crows (Corvus moneduloides), but tests of Ravens (Corvus corax) and Rooks (Corvus frugilegus) have also found problem-solving capabilities. New Caledonian Crows are a common subect for research because they are known to use a variety of tools in the wild. A classic test of bird intelligence involves a piece of food dangling at the end of a string. Multiple bird species can figure out through trial and error how to retrieve the food by pulling the string. Corvids and psittacids retrieve the food so quickly that researchers have suggested that these birds may solve the problem at an advanced level. That is, instead of relying on trial and error, these birds might be able to picture a solution in their minds. Experiments with Ravens and Keas (Nestor notabilis) have provided some hints of advanced problem-solving, but the birds have difficulty retrieving food at the end of a string if the string is crossed by another of the same color. A new PLoS ONE article takes the intelligence tests a step further with New Caledonian Crows. Once again, a piece of meat is suspended at the end of a string. This time, however, the reward is screened from view by a piece of plywood with a small hole in it – just wide enough to pull the meat through. If a crow goes under the board, it can see the food and string. From above the board, it can still see the reward through the hole, but not well enough to judge its distance or whether pulling the string is moving the meat closer. The image shows the setup for this study; this image shows examples of prior experiments. Successful retrieval would require pulling the string part way, stepping on the portion pulled, and then pulling the rest of the string.  The results of this study suggest that crows learn to solve problems through a combination of visual feedback and prior experience with related problems. When crows have an unobstructed view of the string and the meat, they can see the meat get closer each time they pull the string and step on it. Without that visual feedback, they can still solve the problem if they remember that pulling on the string works. This supports the idea that crows solve problems mainly through trial and error and not by insight or causal reasoning. However, the study is not conclusive since one naïve crow did solve the problem and naïve crows that had the benefit of a mirror did not all find the solution. It seems that researchers have found a limit to corvid intelligence. Even if they do not have the benefit of causal reasoning, crows and ravens still best other bird species at the string pulling problem. Some finches can complete a simple string-pulling task but have a much higher error rate, and many finches never figure out the solution. Even naïve crows, however, can solve the simple string problem almost immediately. Their larger forebrains may allow corvids to process and act on visual feedback more quickly than birds in other families.  Taylor, A., Medina, F., Holzhaider, J., Hearne, L., Hunt, G., & Gray, R. (2010). An Investigation into the Cognition Behind Spontaneous String Pulling in New Caledonian Crows PLoS ONE, 5 (2) DOI: 10.1371/journal.pone.0009345For the second winter in a row, hundreds of Brown Pelicans have died or been sickened along the coast of California for reasons that remain unclear.
When found alive, the birds appear hungry and disoriented. But necropsies performed on dead pelicans found that they had been eating, so the casualties don't appear to be from lack of prey. But their stomachs did contain unusual prey, like squid—not the sardines and anchovies they normally dine on.Unfortunately the agency responsible for managing wildlife, the California Department of Fish and Game, has no money for an investigation because of the state's budget crisis. Wildlife rehabilitation organizations, such as the International Bird Rescue Research Center, have been doing their best to rescue and treat sick pelicans. The IBRRC alone has handled 435 sick pelicans since the start of January. However, there have been so many sick pelicans that the groups' resources have been strained to the limit, especially for supplying food for so many pelicans at once.  House Finches at a Feeder Like humans, birds can be infected by various diseases, some of which can be quite contagious. Among feeder birds, House Finches are particularly susceptible to Mycoplasmal conjunctivitis. Avian conjunctivitis causes very noticeable changes to a bird's appearance and behavior. Infected birds appear to have swollen or crusty eyes. Becoming lethargic, they succumb more easily to starvation or predation. A new study examines behaviors that may encourage the spread of conjunctivitis among House Finches. Researchers placed healthy finches into the middle chamber of a partitioned cage with a healthy finch on one side and a visibly diseased finch on the other; all three finches were of the same sex. Food dishes were placed at the edge of each chamber so that the middle finch would have to interact with neighboring finches in order to feed. The researchers then monitored the behavior of the middle finch. While female House Finches fed equally near healthy or diseased finches, males strongly preferred to feed near a diseased finch. This preference may be explained by the symptoms of conjunctivitis. Since the disease produces lethargy, infected males are much less likely to challenge a healthy male for dominance at a feeding station. Feeding near infected individuals thus reduces the energy and social costs of losing such a confrontation. The danger, of course, is that feeding and other interactions with infected individuals is likely to increase a healthy bird's chances of catching disease. Mycoplasmal conjunctivitis is a relatively new disease among House Finches, first documented in 1994. In the context of such a new and contagious disease, male finches' instinct to reduce confrontation may work against their ability to resist disease. Bouwman, K., & Hawley, D. (2010). Sickness behaviour acting as an evolutionary trap? Male house finches preferentially feed near diseased conspecifics Biology Letters DOI: 10.1098/rsbl.2010.0020 |
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