When I started birding several years ago, I eagerly sought whatever resources I could find to help myself learn to identify birds. Of course, I bought a few field guides, with The Sibley Guide to Birds being the one I relied on the most. I also looked for books that went beyond what a traditional field guide offers. One book that proved especially useful was Kenn Kaufman's Advanced Birding, published in 1990 in the Peterson Field Guide series. Kaufman's Advanced Birding taught general principles of bird identification and gave the reader tips on how to separate particularly difficult species groups. Kaufman discussed how to sort out winter loons, scaup, dowitchers, terns, Empidonax flycatchers, chickadees, and fall warblers, among many others. I still refer to the original guide from time to time to refresh my memory on some points.
Kaufman has now created a second edition of Advanced Birding, which is actually a complete rewriting rather than a minor revision. The new edition is about 60% longer than its predecessor (435 vs. 273 pages of written text). It is now part of the growing* Kaufman Field Guide Series instead of the venerable Peterson Field Guide Series. That change brings more than a new label; instead of just black-and-white line drawings, the new edition is illustrated with edited color photographs, with the presentation style familiar from other guides in Kaufman's series. Some of the line drawings from the old edition are included in the new edition to emphasize patterns and shapes rather than colors.
Even a quick scan through the table of contents reveals that the new version is significantly different. Most of the chapters in the first edition treated problematic pairs or small groups of species, such as medium-sized terns or dowitchers. In the new edition, some of these groups or pairs are treated, but more have been dropped or reduced in favor of discussing whole families. Of the 31 chapters in the new edition, 14 start with the phrase "Learning to Identify" followed by the name of a family or order, such as diurnal raptors or warblers. Four chapters on gulls in the older edition have been condensed into a single chapter on the basics of learning gulls. Four chapters on shorebirds are reduced to two, one on shorebird basics and the other on the small Calidris sandpipers (a.k.a. "peeps").
This may sound a loss of content, but most of the same ground is still covered, in one form or another. The "Learning to Identify" chapters present the traits of subgroups within a family or order – usually genus by genus – and then discuss characteristics that are useful for identifying those birds. The most useful characteristics vary from family to family. For example, for waterfowl, Kaufman suggests looking at traits like feeding and flocking behaviors, head and bill structure, upperwing patterns, and flight styles. For warblers, look at things like overall shape, foraging behaviors, wing patterns, and facial patterns. Microhabitat – i.e., where on a lake or marsh a duck forages or where on a tree a warbler gleans insects – can be useful for both groups. Kaufman also discusses potential identification problems, such as molt changing the expected plumage patterns, hybridization, and the introduction of exotic birds (especially among waterfowl).
A further change to the new edition is the addition of several introductory chapters on building identification skills. These cover topics like approaches to bird identification, potential pitfalls that affect all bird groups, bird topography, plumage and molt, using vocalizations and behavior for identification, and techniques for improving skills. Together these make up almost a third of the new Advanced Birding. I read the chapters on bird topography and molt on my way to Cape May a couple weeks ago for bird banding, and they gave me some new insights into what I was seeing on the birds in my hands. I think Kaufman's chapter on molt is particularly worth reading, as he has a talent for making complex concepts easily understandable. It is a simpler and more concise explanation of the terms and concepts for molt than you might find in a book like Molt in North American Birds.
The revised Kaufman Field Guide to Advanced Birding: Understanding What You See and Hear has much to recommend it. The new edition seeks to address a context in which more and more information is available on the finer points of bird identification but not as much on how to fit all those details together. Advanced Birding teaches fundamental skills for recognizing birds in the field that are important for all birders to understand. However, it will be particularly useful to beginner and intermediate-level birders who have some field experience but need help understanding what they see in the field. Birders who wish to improve their identification skills would do well to acquire and read this book. If you can find a copy of the first edition, it is still worth reading, as it contains a lot of fine-grain information and sketches of feather patterns that are not in the new edition.
* Advanced Birding is now the sixth guide in the Kaufman Field Guide series. After my experiences using the butterfly and insect guides, which I consult almost daily in the warmer months, I hope that the series will grow to include separate guides for more insect groups, such as dragonflies and damselflies, moths, beetles, true bugs, and bees and wasps.
This review was based on a review copy provided by Houghton Mifflin Harcourt.
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Tuesday, May 31, 2011
Monday, May 30, 2011
Hobomok Skipper
This is a Hobomok Skipper (Poanes hobomok). It is differentiated from the similar Zabulon Skipper (Poanes zabulon) by having a yellow patch on the underside of its hindwing with one yellow cell that sticks out past the others. It also lacks the prominent yellow spot near the base of the forewing that Zabulon Skippers have. Even though both of these Poanes skippers are common, I see Zabulon Skippers far more than Hobomok Skippers. It is possible that I walk through areas with the Zabulon's host plants more frequently, but I suspect it has more to do with their breeding cycle. Zabulon Skipper has two flights in New Jersey, one peaking in June and the other in August, while Hobomok Skipper has one, in late spring. Since I do most of my butterflying in summer, I probably just miss most of their flight season.
Sunday, May 29, 2011
Summer Azure
The butterfly above is an azure, one of several species in the genus Celastrina. Azures used to be easy; if you were in the eastern U.S. in the spring, you would most likely be looking at a Spring Azure. Over the last decade or two, research has shown that, as with many bird species, "Spring Azure" is actually a complex of related species that are similar in appearance but differ by their larval food plants and flight periods.
This means that azures are now difficult to identify, especially in May when multiple azure species could be flying in New Jersey during any given week. It is a bit easier if you can tie an individual to a larval food plant. The azure above and below appears to be ovipositing on a Gray Dogwood (Cornus racemosa), which is a known food plant for Summer Azure (Celastrina neglecta). The other azure likely to be flying at this time is Cherry Gall Azure (Celastrina serotina), which looks fairly similar to Summer Azure, but whose larvae feed mainly on galls on cherry trees (Prunus sp.), though they will occasionally use other food plants. So I think this is probably a Summer Azure.
One other thing to note here is that azures are notable for feeding on the flowers rather than the leaves of their hosts (with the exception of the Cherry Gall Azure). This azure is giving its larvae a head start by laying its eggs directly on the flower buds.
This means that azures are now difficult to identify, especially in May when multiple azure species could be flying in New Jersey during any given week. It is a bit easier if you can tie an individual to a larval food plant. The azure above and below appears to be ovipositing on a Gray Dogwood (Cornus racemosa), which is a known food plant for Summer Azure (Celastrina neglecta). The other azure likely to be flying at this time is Cherry Gall Azure (Celastrina serotina), which looks fairly similar to Summer Azure, but whose larvae feed mainly on galls on cherry trees (Prunus sp.), though they will occasionally use other food plants. So I think this is probably a Summer Azure.
One other thing to note here is that azures are notable for feeding on the flowers rather than the leaves of their hosts (with the exception of the Cherry Gall Azure). This azure is giving its larvae a head start by laying its eggs directly on the flower buds.
Saturday, May 28, 2011
Raritan Bay Birds
On Thursday morning I visited a couple spots along Raritan Bay to look for migrating waterbirds. The Raritan River flows through my county and opens out into Raritan Bay, which stretches from the mouth of the river at the Amboys out to Sandy Hook. While they do not have the volume of major coastal hotspots like Sandy Hook, the shoreline from South Amboy to Cliffwood Beach offers the best opportunity for coastal birding in Middlesex County.
At South Amboy's Morgan Avenue mudflats, there were sill some lingering winter birds, like the Brant at top and the Bonaparte's Gull above. I expect them to clear out soon. Other than that, the beach was pretty quiet. A couple of Willets waded in the water, and a couple of Semipalmated Plovers picked along the mudflats. A lot of Marsh Wrens were singing in the marsh; they were very active and easily seen. One Least Tern and several Forster's and Common Terns were loafing on the mudflats. Forster's Tern was actually a new county bird for me, which seems odd since they are so common elsewhere, including at inland locations.
Pirate's Cove in Cliffwood Beach had a bit more shorebird diversity. When I came out onto the beach, I saw a Piping Plover fly past. A little further towards the creek, on the near side of a small jetty, there was a small group of shorebirds that included Semipalmated Sandpipers, Spotted Sandpipers, and a Ruddy Turnstone – the latter another county bird. On the other side of the jetty, there were a lot more Semipalmated Sandpipers. Mudflats at the end of the creek held quiet a lot of loafing birds. Most of these were gulls, but there were also some terns, including four Black Skimmers, another new county bird. There were also three American Oystercatchers on the flats and a couple Snowy Egrets wading in the creek.
At South Amboy's Morgan Avenue mudflats, there were sill some lingering winter birds, like the Brant at top and the Bonaparte's Gull above. I expect them to clear out soon. Other than that, the beach was pretty quiet. A couple of Willets waded in the water, and a couple of Semipalmated Plovers picked along the mudflats. A lot of Marsh Wrens were singing in the marsh; they were very active and easily seen. One Least Tern and several Forster's and Common Terns were loafing on the mudflats. Forster's Tern was actually a new county bird for me, which seems odd since they are so common elsewhere, including at inland locations.
Pirate's Cove in Cliffwood Beach had a bit more shorebird diversity. When I came out onto the beach, I saw a Piping Plover fly past. A little further towards the creek, on the near side of a small jetty, there was a small group of shorebirds that included Semipalmated Sandpipers, Spotted Sandpipers, and a Ruddy Turnstone – the latter another county bird. On the other side of the jetty, there were a lot more Semipalmated Sandpipers. Mudflats at the end of the creek held quiet a lot of loafing birds. Most of these were gulls, but there were also some terns, including four Black Skimmers, another new county bird. There were also three American Oystercatchers on the flats and a couple Snowy Egrets wading in the creek.
Friday, May 27, 2011
Loose Feathers #292
Dunlin / Photo by the U.S. Fish and Wildlife Service
Birds and birding news
- Government agencies in the U.S., Canada, and Mexico have put together a bird identification tool called Dendroica that provides images and sound files for each of the species in North America. The taxonomy is a little behind (no split of Winter Wren?), and some species are sparsely represented. Otherwise it looks like a good learning tool. The site is soliciting contributions of image and sound files to fill in the gaps in coverage. (Note: registration is required to contribute.)
- The Great Snipe makes the fastest recorded long-distance, nonstop migration flights of any bird. Some birds cover over 4,000 miles in 96 consecutive hours, with an average speed of 50 mph. The longest known nonstop migration flight is a Bar-tailed Godwit that flew 7,145 miles in nine days, with an average speed of 35 mph.
- A study found that the closely-related Gray Vireo and Plumbeous Vireo alter their songs in different ways when they breed in noisy areas (like gas wells). Plumbeous Vireos shortened their songs and raised the pitch of the lowest parts, while Gray Vireos raised the pitch of the highest parts and sang longer songs.
- A British birder reports on his trip to see a Little Bustard.
- Even though the population of Philippine Eagles is reduced to a few hundred birds, people continue to trap them illegally. (For more on the Philippines, see also this unrelated post on an expedition to research biodiversity on Luzon.)
- A rare white Kiwi chick was born at New Zealand's national wildlife center.
- Seabirds on the coast of Scotland, particularly oystercatchers and eiders, have been recorded laying their eggs in other birds' nests. Unfortunately for the oystercatcher and eider chicks, their parents lay the eggs in the nests of gulls, which are more likely to eat the chick than raise it successfully.
- Gynandromorphs – birds appearing like males on one side of the body and females on the other – can arise due to a chromosome aberration.
- British researchers say that introduced Ring-necked Parakeets intimate other birds – such as Blue Tits and Great Tits – around bird feeders.
- Punctuated Equilibrium: Sparrows show us a new way to have sexes
- 10,000 Birds: A Fistful of British Bird Bloggers
- Sibley Guides: Distinguishing Interior West from Western Taiga White-crowned Sparrows
- Earbirding: Subsong vs. Whisper Song
- The Birder's Report: The American Avocet, A Striking Shorebird
- Birding Dude: Bahamas-banded Piping Plover Breeds in Queens
- Tetrapod Zoology: Birds vs planes II
- A giant water bug was photographed eating a baby turtle. Also, two beetle species, Epomis dejeani and Epomis circumscriptus, have been recorded preying on amphibians.
- The chairman of the House Foreign Affairs oversight subcommittee denies that climate change is happening but recommends clear-cutting rainforests to solve it.
- Meanwhile, in real climate science news, two glaciers in Greenland have lost enough volume in the last decade to fill Lake Erie. A third glacier actually gained mass, but its gain was tiny compared to the loss from the other two glaciers.
- A study of a forest in Massachusetts showed that a warmer climate would stimulate decay and thus release more carbon dioxide into the air, but it would also increase the capacity for trees to sequester carbon. The latter effect would not completely offset the additional carbon release.
- The EPA and NHTSA are introducing new fuel economy labels that will be required for new cars starting in the 2013 model year. The new labels will provide information on each model's fuel efficiency, annual fuel costs, pollutant emissions, and more. They will also include a QR code so buyers with smartphones can get more information.
- A biodiversity program announced its list of the top ten new species discovered in 2010.
- Greg Laden's Blog: Extinction rates have NOT been over-estimated
- Wanstead Birder: More things to do in June: Moths
- The Net Naturalist: Great Tools for Creating a Free Petition for Nature
Thursday, May 26, 2011
Zabulon Skippers
Yesterday and today I recorded my first Zabulon Skippers of the year. They have probably been out a little longer than that, but these were the first that landed long enough for me to get a good look (and photographs!). The photo above is from Donaldson Park; the one below is from the Rutgers Ecological Preserve. Zabulon Skippers (Poanes zabulon) are very common in central New Jersey and fly throughout the summer. To me it seems like the most common skipper in the area, but I am not sure if statistics bear that out. Either way it is a good skipper to learn to recognize.
Wednesday, May 25, 2011
Birding the Preserve
Since my last birding trip there was so productive, I decided to try birding Rutgers Ecological Preserve again yesterday morning. I followed a different route and actually got a little bit lost when one of the trails petered out into a deer trail. (Obviously, I found my way out eventually.) The woods were less productive on this visit than on the previous one. I am not sure if that is a result of overnight weather conditions being unfavorable for the location or just a general slowing down of migration. I recorded about half as many warblers, with a lone Blackburnian being the highlight. Most of the warblers I did hear were Blackpolls or Common Yellowthroats, with some Magnolias in the mix. A Blue-winged Warbler was singing in more or less the same location I heard one on the last visit. Beyond that, there was a nice mix of warm-weather landbirds, but nothing extraordinary.
Here are a few flowers I found growing in the preserve. The above (I think) is a Common Cinquefoil.
This is some sort of blackberry flower. I think it may be a Pennsylvania Blackberry, but I am not entirely sure. This and the cinquefoil were on opposite sides of the trail from each other.
The woods are dark in places, and the morning kept shifting between sunny and cloudy, both of which made photography difficult. It was still worth a try to photograph this Star-of-Bethlehem, though.
Here are a few flowers I found growing in the preserve. The above (I think) is a Common Cinquefoil.
This is some sort of blackberry flower. I think it may be a Pennsylvania Blackberry, but I am not entirely sure. This and the cinquefoil were on opposite sides of the trail from each other.
The woods are dark in places, and the morning kept shifting between sunny and cloudy, both of which made photography difficult. It was still worth a try to photograph this Star-of-Bethlehem, though.
Tuesday, May 24, 2011
Some Red Knot News
Last week, I had the privilege of helping with Red Knot banding in Cape May. A reporter from my local newspaper spent some time with the shorebird banding crew recently and filed a story on the current status of Red Knots. Things are still looking dire, despite some New Jersey's moratorium on the horseshoe crab harvest.
Now the federal government might make a decisive move. The red knot is a priority in a new plan by the U.S. Fish and Wildlife Service to deal with a backlog of 250 animal and plant species proposed to be covered by the Endangered Species Act....
But meanwhile, horseshoe crab harvests in other states might be increased when the Atlantic States Marine Fisheries Commission meets later this year, she added. And scientists are concerned because a key crab survey by Virginia Tech lost its federal funding this year and is just halfway toward raising the $200,000 cost.
Delaware Bay is the big stopover for red knots’ flying north to breeding grounds in Canada, because their migration coincides with the horseshoe crab breeding season that leaves bay beaches littered with nourishing crab eggs. That fattens the birds and gives them energy to push on north and lay eggs, said Niles, chief scientist for the Conserve Wildlife Foundation of New Jersey....
New Jersey shut down its commercial fishery for horseshoe crabs in 2006, culminating years of cutbacks after the take of crabs for fishing bait was blamed for the red knots’ decline. But after 6,000 birds went missing from their South America wintering grounds, researchers think the problem may be down south, Niles said.
Researchers in Argentina reported toxic red tide algae blooms may have killed some birds before they reached their winter quarters, at the southern tip of the continent at Tierra Del Fuego. The drop in the winter count, to 10,000 birds from 16,000, may show growing dangers to the birds all along the western Atlantic and Caribbean shores, said Niles, a former chief of New Jersey’s endangered wildlife program.
Banded shorebirds now carry small flags that can be read with a spotted or from a photographic image. These flags, along with any codes they bear, should be reported at bandedbirds.org. Here is some background information on the website:
“If you are the first one to see the re-sighting, we know the bird is still in the flyway,” said Jeannie Parvin, who manages the website www.bandedbirds.org. “Just that information is very important. It’s not just for red knots, it’s for all the shorebirds.”The website supports the Delaware Bay Shorebird Project, a 15-year effort that has built perhaps the world’s biggest database on migrating shorebirds within a flyway. Like a highway for people, a flyway is a track that birds follow between their southern winter homes and summer nesting grounds in the high Arctic of Canada.
Bandedbirds.org offers pages explaining shorebird research, how to read tags on birds and estimate bird counts. After a one-time registration, contributors can send in sightings that go immediately into a database for researchers to use, Parvin said.
Finally, there has been some research into the feasibility of raising horseshoe crabs from eggs in captivity and releasing them once they are better able to survive predation.
Woodruff works at the university's aquaculture facility in Lower Township, where the staff cultivates oysters. But they are looking to expand their scope to raise horseshoe crabs from eggs for release back into the wild to give the creatures a head-start against hungry predators.
"Everything eats them. Basically, we want to farm them - take their eggs and raise them until they are big enough to survive on their own," Woodruff said.
Such human intervention could solve a conflict between local fishermen and conservationists. New Jersey's ban on crab harvesting remains in place in a bid to build up the number of spawning crabs and their bounty of eggs, which are critical for feeding rare shorebirds such as red knots that gather on the bay to fatten up during their epic migrations from the Arctic to South America.
Daniel Hernandez, an assistant professor at The Richard Stockton College of New Jersey, counts crab eggs on the beach each year for his ongoing research. The Stone Harbor resident said egg counts have dropped precipitously from their historic levels....
A 2009 study in the journal BioScience, which Hernandez took part in, said that in 1990 more than 100,000 crab eggs per square meter were found on Delaware Bay beaches.
"Now they have 5,000," he said.
I hope that works to rebuild their numbers because the number of horseshoe crabs eggs is critically low to support Red Knots and the other shorebirds that depend on them. The same news article mentions that there will be horseshoe crab tagging sessions open to the public at 8:30 pm on May 31 and June 2 at Kimbles Beach in Cape May NWR. If you're in the area, it might be worth checking out.
Monday, May 23, 2011
Ants Fighting
Hummingbird feeders can be an effective way to attract hummingbirds to a yard, particularly if there are also some shrubs where the birds can rest and appropriate flowering plants where they can feed. The feeders in my backyard attract hummingbirds occasionally – usually during migration or post-breeding dispersal. On most days, the feeders seem to attract more insects than hummingbirds. Ants in particular find them a good place to visit.
Yesterday, I noticed that two of the ants on top of the feeder seemed to be having a dispute. I am not sure what was at stake; it is possible that they were workers representing two different nests or colonies. The ants had locked their jaws together and were pushing each other with their antennae waving at each other.
On it went, with the ants pushing each other all around the top of the feeder. At times their movements seemed almost like a dance. Finally, one seemed to gain the upper hand and pushed the other off the feeder.
Yesterday, I noticed that two of the ants on top of the feeder seemed to be having a dispute. I am not sure what was at stake; it is possible that they were workers representing two different nests or colonies. The ants had locked their jaws together and were pushing each other with their antennae waving at each other.
On it went, with the ants pushing each other all around the top of the feeder. At times their movements seemed almost like a dance. Finally, one seemed to gain the upper hand and pushed the other off the feeder.
Sunday, May 22, 2011
Pink Lady's Slipper
This was one of two pink lady's slipper plants that I saw at Cheesequake State Park yesterday morning. The other had no flower on it, but this one was in full bloom. The lady's slippers were protected by a temporary fence. I am not sure if the fence was meant to exclude deer or people, but either way, it ensured that the flowers would be there for anyone passing by to enjoy. Apparently Cheesequake hosts an especially good population of lady's slippers for New Jersey.
There were some birds around, but not as many migrants as I expected. There were a lot of Blackpoll Warblers, as is typical of late May; other than that the only migrant warbler species I detected was a Magnolia Warbler. A lot of Common Yellowthroats and Ovenbirds are setting up breeding territories, though. Numerous Marsh Wrens – actually a county bird for me – were singing in the park's extensive salt marsh. The best place to see and hear them is from the boardwalk trail near the lake parking lot. From the same trail, I could see an immature Northern Harrier cruising over the distant marsh. As it crossed the creek, it would flush Willets and other shorebirds, some of which seemed to attack the harrier – something I had not seen a sandpiper do before.
There were some birds around, but not as many migrants as I expected. There were a lot of Blackpoll Warblers, as is typical of late May; other than that the only migrant warbler species I detected was a Magnolia Warbler. A lot of Common Yellowthroats and Ovenbirds are setting up breeding territories, though. Numerous Marsh Wrens – actually a county bird for me – were singing in the park's extensive salt marsh. The best place to see and hear them is from the boardwalk trail near the lake parking lot. From the same trail, I could see an immature Northern Harrier cruising over the distant marsh. As it crossed the creek, it would flush Willets and other shorebirds, some of which seemed to attack the harrier – something I had not seen a sandpiper do before.
Saturday, May 21, 2011
The Face of Weevil
I recently found this weevil on a shrub in the backyard. I think it belongs to the genus Curculio, but I am not sure of the species. Species in that genus often have extremely long snouts, which may be longer than the rest of the body in some females. Weevils in Curculio are associated with nut-bearing trees, such as oaks, hickories, walnuts, birches, and hornbeams. Females use their long snouts to bore into a developing nut or acorn and then lay their eggs inside. Grubs hatch inside the nut or acorn and eventually fall to the ground and mature in the soil.
Prominent Curculio species include Curculio proboscideus, the Large Chestnut Weevil, and Curculio caryae, the Pecan Weevil. I am not sure which species this is, so I am not sure which tree hosts it. The closest potential host to where I found it is a Pin Oak. Farther away, there is a Black Walnut, which may also host Curculio weevils. Either way, as far as I can tell, there is no imminent threat of an infestation. So it is just another interesting backyard insect.
Prominent Curculio species include Curculio proboscideus, the Large Chestnut Weevil, and Curculio caryae, the Pecan Weevil. I am not sure which species this is, so I am not sure which tree hosts it. The closest potential host to where I found it is a Pin Oak. Farther away, there is a Black Walnut, which may also host Curculio weevils. Either way, as far as I can tell, there is no imminent threat of an infestation. So it is just another interesting backyard insect.
Friday, May 20, 2011
Loose Feathers #291
Going Places – Bay-breasted Warbler / Photo credit: Janet M. Hug (JKissnHug)
Birds and birding news
- When scientists attached video cameras to the backs of juvenile Brown Boobies, the recorded footage showed that they learned how and where to forage from other seabirds. There is a short sample video at the link.
- Re-examination of a Triassic-era fossil from China pushed back the date for the split between the crocodile and bird evolutionary lineages.
- Two environmental organizations are suing the owners of Toronto buildings that are most hazardous to birds. The buildings have caused the deaths of 7,000 birds in the last decade.
- Kauai is a good place to see endemic Hawaiian birds, but many of them are disappearing.
- The population of Rose-ringed Parakeets has recently exploded in Great Britain, rising from 1,500 in 1995 to over 30,000 now.
- Experiments show that African Grey Parrots can cooperate to complete a task.
- To some observers, the rise of baby bird webcams is a sign of biophilia.
- Officials in Newcastle are considering building a kittiwake tower to move breeding kittiwakes off the Tyne Bridge.
- 10,000 Birds: A Question of Migration
- Bird Canada: 84 Burrowing Owls Released to the Wild
- March of the Fossil Penguins: Featherless Penguin Gets a Helping Hand from Humans
- BES Group: Black Scoter takes a mollusc
- Ecobirder: Splish Splash!
- The Freiday Bird Blog: Tom Parsons Passes
- The Nightjar: 50 Years of Warbler Springs – Have they really changed?
- The Nemesis Bird: Golden Eagle vs Raven
- A new paper argues that extinction rates based on habitat loss have been overestimated, perhaps by as much as 160%, because many estimates use too crude of a model. However, habitat loss is still a serious issue and contributes to many extinctions.
- Of course, extinctions are about more than habitat loss; other issues include loss of critical food supplies or the spread of deadly diseases (such as the chytrid fungus that is killing many amphibians).
- A red-crested tree rat (Santamartamys rufodorsalis) was recently spotted outside a lodge in El Dorado Nature Reserve in northern Colombia; it was the first time a member of that species had been seen since 1898. (Follow the link for photos of the cute tree rat.)
- Recent calculations conclude that we have yet to discover 33% of amphibians and 3% of land mammals, which put together is about 3,000 species. The trick, of course, is to find them before they go extinct, which is a serious concern since undiscovered species are likely to be rare or in remote and threatened areas.
- Federal officials are trying to determine whether a proposed Christo installation in Colorado would harm bighorn sheep.
- National Geographic has photos of America's top ten endangered rivers. Really, there are probably rivers that are currently worse off, but these will all be subject to major decisions that will effect them for better or worse.
- Demand for green roofs is rising in New York City. If enough building owners install and maintain them, green roofs could ease the strain on the city's storm drains and sewer system.
- Periodical cicadas emerge in 13- and 17-year intervals because prime-number cycles make it harder for potential predators to take advantage of them. Bora explains why we are unlikely to learn the cicadas' mechanism for emerging in prime number cycles.
- Southern U.S. forests are falling to the paper industry and suburban development; unlike the rest of the country, very little southern forest is protected.
- Bug Girl's Blog: Debugging Grace Hopper
- Myrmecos: Photographing insects with a point & shoot digicam
Thursday, May 19, 2011
Some More Shorebird Photos
These are a few additional photos that I took on Saturday, but that did not fit into my post on shorebird banding yesterday. Up above, a group of Dunlin pause in the surf, with a Semipalmated Sandpiper standing by.
A Dunlin forages in the foreground while Red Knots stand in the surf.
A familiar trio from Reed's Beach: Red Knot, Laughing Gull, and Dunlin.
A Semipalmated Sandpiper picks through beach litter for morsels.
A Laughing Gull stands in the surf.
Speaking of Laughing Gulls, this is what Reed's Beach looked liked on Sunday morning. Cape May County has one of the largest Laughing Gull breeding areas in the world in its back bay marshes along the eastern side of the peninsula. Apparently a lot of those nests got flooded out in the last week because of recent high tides, made higher than normal by their proximity to the full moon on Tuesday. As a result, a lot of those gulls were hanging out in the horseshoe crab spawning areas along the Delaware Bay instead of tending to their nests in the marshes.
A Dunlin forages in the foreground while Red Knots stand in the surf.
A familiar trio from Reed's Beach: Red Knot, Laughing Gull, and Dunlin.
A Semipalmated Sandpiper picks through beach litter for morsels.
A Laughing Gull stands in the surf.
Speaking of Laughing Gulls, this is what Reed's Beach looked liked on Sunday morning. Cape May County has one of the largest Laughing Gull breeding areas in the world in its back bay marshes along the eastern side of the peninsula. Apparently a lot of those nests got flooded out in the last week because of recent high tides, made higher than normal by their proximity to the full moon on Tuesday. As a result, a lot of those gulls were hanging out in the horseshoe crab spawning areas along the Delaware Bay instead of tending to their nests in the marshes.
Wednesday, May 18, 2011
Shorebird Banding in Cape May
As many readers are aware, conservation of shorebirds that use the Delaware Bay as a migratory stopover is a pressing issue. Many species, such as Red Knots and Ruddy Turnstones, time their migration to arrive at the bay just as horseshoe crabs are laying their eggs on the beaches. Shorebirds feed on those eggs to regain the weight they lost during their flights from wintering grounds in South America and prepare for another long flight to their Arctic breeding grounds. For a long time this arrangement worked well, but in the 1990s, overharvesting of horseshoe crabs (used for fishing bait and medical research) caused a crash in the Red Knot population. States have taken some steps to limit the horseshoe crab harvest (including New Jersey's legislative moratorium), but the Red Knot's survival remains tenuous. The population has fallen enough to earn the Red Knot a place on the USFWS's candidate list but so far it has not been listed as threatened or endangered by the federal government.
An international effort is underway to monitor the remaining population and push for conservation of the habitats and resources the Red Knots need. Part of that is an ongoing banding program to study how birds use stopover sites and what migration routes they use. My friend Mary (whom I met through DC Audubon) knows some of the banders from her time in Australia, so she got invitations for the two of us to participate in a banding session this past weekend. Because of weather and tides, it turned out that Saturday was our best chance to participate, so we made sure to be at Reed's Beach early in the morning, even though we both arrived in Cape May rather late the previous night.
You can see how shorebirds are banded in a video I linked on this blog a few years ago. That shows a different set of banders in a different location, but the methods for capture and processing are essentially the same. The banding team prepares a net and disguises it as carefully as possible. Once enough shorebirds are in front of the net, the team fires cannons that propel the net over the birds. Some birds will escape, but many will be caught under the net. The banding team hurries to extract the birds from under the net as quickly as possible, so as to avoid unnecessary stress or injuries to the birds. Once all the birds are out of the net and into shaded containers, the banders can sit down and process them.
On Saturday, the captured birds went through several steps before their release. First they were banded and marked with coded tags to make it easier to recognize individuals in the field without recapturing them;* then a series of measurements were taken: weight, wing chord, and bill and head length; finally, feather samples were taken for lab analysis. One person recorded all of the codes and measurements for each bird. I was last in line, so I held each bird while another person snipped some feathers (one wing covert and two breast feathers), and then I released it. I think I probably handled a few dozen Red Knots in the course of the morning, though I was not keeping count.
It was really cool to hold the Red Knots and see them up close. One thing I had not realized when I looked at them through binoculars was just how intricate the patterns on their backs are. Their scapulars in particular have dark brown lines dividing each feather into sixths; the middle part of the feather is tinged with rufous while the tip is white. Meanwhile, their rumps are etched with fine barring, and their undertail coverts are speckled. The Red Knots were also smaller than I expected; I guess they look larger to me through binoculars than they do in the hand. A lot of these birds were recent arrivals, though, so it is possible I would get a different impression once they had time to gorge themselves on horseshoe crab eggs.
As I mentioned in yesterday's post, Mary and I went to Heislerville in the afternoon and evening to find a Curlew Sandpiper. Once we had found it, we helped with another banding project that is monitoring some of the species using the impoundments. That project is mainly concerned with Semipalmated Sandpipers, but it also bands Short-billed Dowitchers, Dunlin, and other shorebird species that happen to get tangled in the nets. Mary helped extract shorebirds from the nets, while I ferried birds from the nets to the banders or held nets so that they would not blow on a bird during the extraction process. Once again I was impressed by the birds' small size; the Semipalmated Sandpipers were especially tiny.
I really enjoyed my experience with shorebird banding this weekend, and I hope to do more of it when I have the chance.
* If you happen to see a Red Knot (or other shorebird) with color markings or a colored flag with an alphanumeric code on it, please report it to bandedbirds.org.
An international effort is underway to monitor the remaining population and push for conservation of the habitats and resources the Red Knots need. Part of that is an ongoing banding program to study how birds use stopover sites and what migration routes they use. My friend Mary (whom I met through DC Audubon) knows some of the banders from her time in Australia, so she got invitations for the two of us to participate in a banding session this past weekend. Because of weather and tides, it turned out that Saturday was our best chance to participate, so we made sure to be at Reed's Beach early in the morning, even though we both arrived in Cape May rather late the previous night.
You can see how shorebirds are banded in a video I linked on this blog a few years ago. That shows a different set of banders in a different location, but the methods for capture and processing are essentially the same. The banding team prepares a net and disguises it as carefully as possible. Once enough shorebirds are in front of the net, the team fires cannons that propel the net over the birds. Some birds will escape, but many will be caught under the net. The banding team hurries to extract the birds from under the net as quickly as possible, so as to avoid unnecessary stress or injuries to the birds. Once all the birds are out of the net and into shaded containers, the banders can sit down and process them.
On Saturday, the captured birds went through several steps before their release. First they were banded and marked with coded tags to make it easier to recognize individuals in the field without recapturing them;* then a series of measurements were taken: weight, wing chord, and bill and head length; finally, feather samples were taken for lab analysis. One person recorded all of the codes and measurements for each bird. I was last in line, so I held each bird while another person snipped some feathers (one wing covert and two breast feathers), and then I released it. I think I probably handled a few dozen Red Knots in the course of the morning, though I was not keeping count.
It was really cool to hold the Red Knots and see them up close. One thing I had not realized when I looked at them through binoculars was just how intricate the patterns on their backs are. Their scapulars in particular have dark brown lines dividing each feather into sixths; the middle part of the feather is tinged with rufous while the tip is white. Meanwhile, their rumps are etched with fine barring, and their undertail coverts are speckled. The Red Knots were also smaller than I expected; I guess they look larger to me through binoculars than they do in the hand. A lot of these birds were recent arrivals, though, so it is possible I would get a different impression once they had time to gorge themselves on horseshoe crab eggs.
As I mentioned in yesterday's post, Mary and I went to Heislerville in the afternoon and evening to find a Curlew Sandpiper. Once we had found it, we helped with another banding project that is monitoring some of the species using the impoundments. That project is mainly concerned with Semipalmated Sandpipers, but it also bands Short-billed Dowitchers, Dunlin, and other shorebird species that happen to get tangled in the nets. Mary helped extract shorebirds from the nets, while I ferried birds from the nets to the banders or held nets so that they would not blow on a bird during the extraction process. Once again I was impressed by the birds' small size; the Semipalmated Sandpipers were especially tiny.
I really enjoyed my experience with shorebird banding this weekend, and I hope to do more of it when I have the chance.
* If you happen to see a Red Knot (or other shorebird) with color markings or a colored flag with an alphanumeric code on it, please report it to bandedbirds.org.
Tuesday, May 17, 2011
Seeing a Curlew Sandpiper
This past weekend I was in Cape May, primarily to participate in shorebird banding, but also to see any rare birds that might be around. I was especially eager to see one of the several Curlew Sandpipers that have been frequenting the impoundments at Heislerville. This is a species I have missed on past visits to Heislerville. Plus, who can resist a sandpiper with a long, down-curved bill and a bright red breast? Not me!
During migration seasons, Heislerville attracts thousands of shorebirds, especially at high tide. As the tide rises, more and more shorebirds fly in from nearby feeding areas along the Delaware Bay and its tributaries. On Saturday evening, there were probably 10,000 or more in the main impoundment by high tide. From what I could see, the plurality were Dunlin, but there were substantial numbers of dowitchers and peeps as well. The shorebirds feed and rest a short distance from the dike, which allows for excellent views of these common shorebirds.
One of the other birders present announced that the Curlew Sandpiper was foraging in an exposed area with some of the peeps. My friend Mary found it in the scope before I found it with binoculars and let me have a look at it. The bird was a bit paler than I expected, but its bill was obviously down-curved and its overall pattern was noticeably different from other, more common shorebirds. It was convenient to have Dunlin and Short-billed Dowitchers nearby for comparison.
One other species of interest in the main impoundment was Red Knot. A group of about ten was among the thousands of other shorebirds. One of the group was banded and wore a light green flag with the code 3CP. By entering the code at bandedbirds.org, I found out that this bird was banded at Mispillion Harbor in Delaware in 2009 and was recaptured at Kimble's Beach in New Jersey in 2010. That means that this individual has made it back to Delaware Bay three years in a row as part of its annual round trip from southern South America to the Arctic and back.
During migration seasons, Heislerville attracts thousands of shorebirds, especially at high tide. As the tide rises, more and more shorebirds fly in from nearby feeding areas along the Delaware Bay and its tributaries. On Saturday evening, there were probably 10,000 or more in the main impoundment by high tide. From what I could see, the plurality were Dunlin, but there were substantial numbers of dowitchers and peeps as well. The shorebirds feed and rest a short distance from the dike, which allows for excellent views of these common shorebirds.
One other species of interest in the main impoundment was Red Knot. A group of about ten was among the thousands of other shorebirds. One of the group was banded and wore a light green flag with the code 3CP. By entering the code at bandedbirds.org, I found out that this bird was banded at Mispillion Harbor in Delaware in 2009 and was recaptured at Kimble's Beach in New Jersey in 2010. That means that this individual has made it back to Delaware Bay three years in a row as part of its annual round trip from southern South America to the Arctic and back.
Monday, May 16, 2011
Strutting Turkey
This male Wild Turkey was displaying to the cars passing along US Route 9 in Atlantic County yesterday afternoon. It walked very deliberately out into the road and gobbled at the cars as they stopped. Eventually someone came out of one of the nearby houses to shoo it away since it was blocking traffic.
Sunday, May 15, 2011
Oriole Constructing a Nest
Last week, on one of the days that I walked around my patch, I happened to see an oriole that was scolding and carrying nesting material in its bill. I stood still and watched it, and the bird eventually approached its nest site. After scolding a bit more, it flew down to the branch above its nest and placed the material into the nest.
Unlike birds that build cup nests, orioles prefer hanging nests. The top of the nest is connected to a branch, often at a fork, and usually on the outer tip. The rest hangs below like a basket, wider at the bottom than at the top. This bird is a female oriole, and usually female orioles build their nests without help from the males.
Unlike birds that build cup nests, orioles prefer hanging nests. The top of the nest is connected to a branch, often at a fork, and usually on the outer tip. The rest hangs below like a basket, wider at the bottom than at the top. This bird is a female oriole, and usually female orioles build their nests without help from the males.
Saturday, May 14, 2011
Loose Feathers #290
Worm-eating Warbler / Photo by Dan Sudia (USFWS)
Note: This week's edition is a day late due to a massive Blogger outage that prevented me from writing and scheduling it on Thursday night, as I usually would. So it appears on Saturday morning instead. Next week, it should appear at the regularly-scheduled time.
Birds and birding news
- The Interior Department settled a number of endangered species lawsuits by promising to make listing decisions for 251 candidate species. One of the species on the waiting list is the Greater Sage Grouse.
- A pair of Ospreys stopped construction in Anacostia Park in Washington, DC, when they built a nest on top of a crane. Work will be resumed once the birds vacate the nest.
- Even though Prospect Park attempted to prevent Canada Geese from breeding by addling their eggs, one goose family hatched four goslings this spring.
- Male Spotted Bowerbirds mimic sounds they hear while they are under stress from predators or bully species.
- Emperor Penguins are able to make prolonged dives by regulating the amount of oxygen they send to their muscles. For especially deep dives, they can cut off the flow of oxygen to muscles in order to leave more for other organs.
- Antarctic penguins are struggling to adapt to a warming climate.
- According to new research, Barred Owls are more abundant in the Pacific Northwest than previously recognized; this finding could have significance for Northern Spotted Owl conservation.
- Tanzania plans to mine in Lake Natron, one of the world's most important breeding grounds for Lesser Flamingos.
- Older Blue-footed Boobies have trouble reproducing successfully, as their offspring are more likely to develop genetic illnesses. Foot color fades are a booby ages, so females may be able to choose younger mates on that basis.
- 10,000 Birds dedicated this week to posts about Neotropical wood warblers. It produced a lot of good contributions. Some of the more interesting posts include: The Vulnerable Cerulean Warbler, The Lost Warblers of the Farallon Islands, Wood-Warbler Watching in New York City, Rev. Bachman’s Lost Warbler, and A Revised Wood-Warbler Taxonomy Primer.
- Sibley Guides: Intergradation between Mexican Duck and Mallard in Arizona
- Tails of Birding: My Favorite Warbler
- The Birder's Library: birdJam HeadsUp Warblers & HeadsUp Sparrows
- ABA Blog: Spring Migration at Perk's National Forest
- birdspot: Phthalocyanine
- Fotoportmann: Warblers and other micro Birds: Central Park, NYC
- Mike's Birding and Digiscoping Blog: Warbler Parade
- Daily Kos: Dawn Chorus: A Riddle.
- Climate change is a factor in higher food prices, with Russia, Turkey, and Mexico being among the worst affected.
- A report to Congress by the National Research Council urges that the U.S. should begin greenhouse gas emissions reductions as soon as possible to avoid the worst effects of climate change.
- Feral cats can pass their diseases on to wildlife, even in remote wild areas.
- Bug Girl’s Blog: Hoppers, Hats, and Homology
Thursday, May 12, 2011
Local Birding Notes
In yesterday's blog post, I posted photos of a Baltimore Oriole that I have taken the day before. Shortly after I took those photos, I came across a Prothonotary Warbler – very unusual for my county – in Donaldson Park's dump area. It perched briefly at the top of a small tree and allowed a thorough look before it disappeared back into the brush. Unfortunately I was not able to re-find it, despite going back behind the dump to look for it. Otherwise Tuesday morning's birding was unremarkable.
Yesterday morning I walked through the Rutgers Ecological Preserve for the first time in a while. It is an attractive destination for migrating birds because it contains one of the few uncut tracts of old-growth forest in the area, and even the second-growth forest stands out against the surrounding landscape, which is mostly developed. As soon as I walked into the preserve, I could hear forest species singing – Blackpoll Warbler, Scarlet Tanager, Wood Thrush, Red-eyed Vireo, Black-throated Green Warbler and Worm-eating Warbler all in relatively short succession. There were a lot of Ovenbirds scattered throughout the preserve. Near the former ammunition bunkers, I saw a female Rose-breasted Grosbeak carrying nesting material. On the other side of the depot, a Blue-winged Warbler was singing in the scrubby area.
I encountered a few more patches of bird activity as I followed the main trail to the other side of the preserve and back. Overall, I recorded 15 warbler species (pretty good for Middlesex County), including Nashville, Black-throated Blue Warbler, Chestnut-sided Warbler, Northern Parula, Magnolia Warbler, and American Redstart. A lot of Yellow-rumped Warblers are still around, too. One Veery was down near the creek. A really close look at a pair of Scarlet Tanagers was a great way to close out the walk.
Yesterday morning I walked through the Rutgers Ecological Preserve for the first time in a while. It is an attractive destination for migrating birds because it contains one of the few uncut tracts of old-growth forest in the area, and even the second-growth forest stands out against the surrounding landscape, which is mostly developed. As soon as I walked into the preserve, I could hear forest species singing – Blackpoll Warbler, Scarlet Tanager, Wood Thrush, Red-eyed Vireo, Black-throated Green Warbler and Worm-eating Warbler all in relatively short succession. There were a lot of Ovenbirds scattered throughout the preserve. Near the former ammunition bunkers, I saw a female Rose-breasted Grosbeak carrying nesting material. On the other side of the depot, a Blue-winged Warbler was singing in the scrubby area.
I encountered a few more patches of bird activity as I followed the main trail to the other side of the preserve and back. Overall, I recorded 15 warbler species (pretty good for Middlesex County), including Nashville, Black-throated Blue Warbler, Chestnut-sided Warbler, Northern Parula, Magnolia Warbler, and American Redstart. A lot of Yellow-rumped Warblers are still around, too. One Veery was down near the creek. A really close look at a pair of Scarlet Tanagers was a great way to close out the walk.
Wednesday, May 11, 2011
Tuesday, May 10, 2011
Grosbeak and Friends
Spring migration keeps chugging along, and even when weather conditions are not particularly favorable for good flights over the east coast, it is still possible to find new birds locally. Some birds, like the Red-winged Blackbird above, seem to be settling into their breeding territories on my local patch. It would not surprise me if some of the blackbirds have already nested. Yellow Warblers, Common Yellowthroats, Warbling Vireos, and Baltimore Orioles seem to be claiming territories, too. I have heard singing males of each species consistently in the same places for at least a week now.
Great-crested Flycatchers arrived on my patch more recently, but one has been hanging around the same grove for a few days. I am not sure if it is the same individual. A few others were present yesterday, in different parts of the park and calling from across the river.
One bird that is unlikely to nest in the park is this Rose-breasted Grosbeak. I see them on my patch rarely, and only during migration. There are other places locally where they would be likely to find better habitat, though. In the case of this bird, it was the song rather than the flashy colors that caught my attention. That usually seems to be the case – despite its white undersides and flashy red collar, these birds blend in quite well with the canopy. Another song that caught my attention was that of a Chestnut-sided Warbler. I did not manage to track it down to admire its spring plumage, but it was a new bird for me in Middlesex County.
Great-crested Flycatchers arrived on my patch more recently, but one has been hanging around the same grove for a few days. I am not sure if it is the same individual. A few others were present yesterday, in different parts of the park and calling from across the river.
One bird that is unlikely to nest in the park is this Rose-breasted Grosbeak. I see them on my patch rarely, and only during migration. There are other places locally where they would be likely to find better habitat, though. In the case of this bird, it was the song rather than the flashy colors that caught my attention. That usually seems to be the case – despite its white undersides and flashy red collar, these birds blend in quite well with the canopy. Another song that caught my attention was that of a Chestnut-sided Warbler. I did not manage to track it down to admire its spring plumage, but it was a new bird for me in Middlesex County.
Monday, May 09, 2011
Invertebrates at Bowman's Hill
A woodland with as many native wildflowers as Bowman's Hill Wildflower Preserve is going to attract lots of invertebrates, and that was the case on Saturday. One azalea bush in particular was a magnet for pollinators. I saw my first Monarch of the year drinking from one of its flowers. This individual looks a little worn and faded, so it might have migrated from further south. There were a few other butterflies around it too, including a Juniper Hairstreak and a Spicebush Swallowtail.
Bees were around the azalea flowers, too, including this sweat bee (probably Augochlora pura). There were a few other bees, including some bumble bee species, visiting the flowers as well. The bush also attracted the first Hummingbird Clearwing moth I have seen this year.
This Six-spotted Tiger Beetle was basking in the bright sunlight on the stone bridge.
This fishing spider (probably Dolomedes vittatus) was on a rock at the edge of a small stream. I am not sure if it was there to bask in the sunlight or if it was waiting for prey to come along. Perhaps it was a bit of both.
Bees were around the azalea flowers, too, including this sweat bee (probably Augochlora pura). There were a few other bees, including some bumble bee species, visiting the flowers as well. The bush also attracted the first Hummingbird Clearwing moth I have seen this year.
This Six-spotted Tiger Beetle was basking in the bright sunlight on the stone bridge.
This fishing spider (probably Dolomedes vittatus) was on a rock at the edge of a small stream. I am not sure if it was there to bask in the sunlight or if it was waiting for prey to come along. Perhaps it was a bit of both.