Thursday, August 16, 2007

More penguins

More recent penguin research documents the bio-accumulation of organic pollutants in the soil of Adelie Penguin colonies. As reported in the Journal of Environmental Monitoring, the authors found concentrations of persistent organic pollutants such as DDT, DDE, and PCB's 10 to 100 times higher in soils of penguin colonies than in nearby reference areas. Although these pollutants have been known in penguins, where they bio-accumulate from pollutants distributed to the Antarctic through long-range atmospheric transport from other areas, this research suggests that these birds further bio-accumulate these pollutants at their colonies through defecation. Thus, the soils around the penguin colonies are "hot spots" of persistent organic pollutants.

Other penguin items of note include this National Geographic video here with a couple of brief shots of yours truly counting penguins. This video is from two years ago when Boyd Matson accompanied us on the National Geographic Endeavour and it includes a number of the Oceanites researchers in the video. It is a fairly good if not brief overview on the current status of penguins on the Antarctic Peninsula.

Oh yeah, and one more thing. Those penguins that are occasionally reported off the Pacific coast of North America are probably unwilling hitchhikers from farther south. An article by A. N. Van Buren and P. Dee Boersma in the Wilson Journal of Ornithology examined the occurrences of penguins north of the equator (excluding the Galapagos Penguin which nests on Isabella Island in the Galapagos just north of the line). Although penguins are known to move very long distances (I once found a Magellanic Penguin, which normally breeds in southern South America, near Palmer Station on the Antarctic Peninsula), these movements are all within cold or cold waters of the southern hemisphere. They argue against natural vagrancy for the northern observations because a penguin would likely overheat in the equatorial waters before finding cold waters north of the equator.
The authors explain that the occurrences of these birds is probably due to intentional capture and subsequent release by fishermen moving from the cold southern waters to the cold northern waters and provide information on a number of penguins found on fishing vessels in northern waters.

Laurence Roosens, Nico Van Den Brink, Martin Riddle, Ronny Blust, Hugo Neelsa and Adrian Covaci. 2007. Penguin colonies as secondary sources of contamination with persistent organic pollutants. Journal of Environmental Monitoring 9 pp. 822-825.

A. N. Van Buren and P. Dee Boersma. 2007. Humbolt Penguins (Spheniscus humbolti) in the Northern Hemisphere. The Wilson Journal of Ornithology 119(2)284-288.

Spragues Pipit

A few photos from a day in the field. A Sprague's Pipit gallery

Tuesday, August 14, 2007

Three New Blogs

I recently added three new blogs and one website to my sidebar and I would like to point them out.

The first is a young artist, Martí Rodríguez Franch, who does wonderful field sketches. I find I like field sketches often much more than final paintings because there is so much more of the bird and the art in those sketches.

The next blog is entirely in French and is titled De Temujin...a Gensis Khan. It is blog about a couple's journey across Mongolia and central Asia. Those of you who can read French will get much more out of it than me but I really enjoy the photos. They recently had a pretty nasty accident with their van and my lack of French has limited my knowledge about what they are going to do now.

The third blog is Camera Trap Codger, a great blog about a retired biologists who sets camera traps in his neighborhood to record the coming and goings of the neighbors he rarely sees; the wildlife.

The website I added is Ian Lewington's website for his artwork. I came across this site thanks to Martí. I first came across Ian's work when he illustrated this book. The print below is one of my favorites he currently has for sale.

Sunday, August 12, 2007

Penguin Interlude Part II

A paper in the Proceedings of the National Academy of Sciences by Steve Emslie and William Patterson recently prompted a New York Times article and mention in the Querencia blog.
This paper discusses changes in Adelie Penguin diets over the last 38000 years by examining eggshell remains found in detritus of historic and present Adelie Penguin colonies. The stable isotope values of carbon and nitrogen in over 270 eggshells suggested that there was an abrupt shift in the diet of Adelie Penguins throughout their range from fish to krill about 200 years ago. The change in diet coincides with the discovery of the Antarctic Peninsula and subsequent exploitation of the Antarctic Fur Seals in the area.
I will provide a bit of the back-story on this paper. Sealing began in the sub-Antarctic islands in 1784 and on the Antarctic peninsula in 1819 although sealers were probably working the peninsula before that but not giving away the location of their hunting grounds (you thought it was an untouched, pristine continent didn't you - just wait). During the 1820-21 austral summer 55 to 60 sealing ships were in the South Shetland Islands and they took an estimated 1/4 million seals in 3 months. Millions of seals had already been killed in the Sub-Antarctic islands and by 1825 the seals were gone and the Antarctic Fur Seal was believed extinct.
Antarctic Fur Seal on whaler's cross. South Georgia.

Whalers came next but the harvest of whales and whale-like seals was limited to the slower more accessible species such as the Southern Right Whale and Elephant Seals. By the early 1900's however, with the advent of the explosive harpoon and faster ships, the rorqual whales which were previously too fast to catch became the preferred target. Shore stations for processing whales were established in 1904 on South Georgia and by 1910 about 12,000 whales were harvested. In 1926 the first floating factory ship began working in the Antarctic waters. Nearly 30,000 Blue Whales alone were killed during the 1930-31 season. Blue Whales, Fin Whales, Sei Whales and Minke Whales were harvested in turn and in 1940, 40,000 whales were killed. (See here for more history and here and here for more historical whaling information).

The above graph shows the numbers and species of whales taken in Antarctica from 1904-05 to 1980-81. See here.

In 1985, Richard M. Laws, then the head of the British Antarctic Survey, published a paper in American Scientist entitled "The Ecology of the Southern Ocean". In his paper he estimated that whales, a pre-harvest biomass of nearly 45 million tons, had probably consumed 190 million tons of krill in addition to 14 million tons of squid and 5 million tons of fish each year. He further estimated that my 1973 the whale biomass was about 9 million tons and they consumed 43 million tons of krill. This left a "surplus" of 150 million tons of krill annually (italics are mine). He surmised that this surplus had a profound affect on the ecology of Antarctic animals and in particular had increased populations of Adelie, Chinstrap and Macaroni Penguins. In addition, during this time the Antarctic Fur Seal reappeared from the mist of extinction and prospered in the absence of the large whales. They probably now exceed their pre-exploitation population. His premise certainly seemed logical.

However, in 1992, a host of Antarctic researchers then affiliated with the Point Reyes Bird Observatory, published an article in Polar Biology suggesting that the krill surplus theory was not responsible for changes in penguin populations at all. The title of their paper, "Increases in Antarctic penguin populations: reduced competition with whales or a loss of sea ice due to environmental change" suggested it was an either/or proposition and that they believed that much of the observed changes in penguin populations were not due to reduced competition for food but were instead a result of changes in the amount and duration of Antarctic sea ice. They provided very compelling evidence that the amount and duration of sea ice had more influence on the relative populations of Chinstrap and Adelie Penguins than the surplus of krill.

So where does this recent evidence of a shift in Adelie Penguin diet from fish to krill during the time of heavy exploitation of krill eating animals leave us?

I began my Antarctic penguin studies during the time of the sea ice theory and in fact I had two of the authors as advisers at one time or another. But I was never comfortable ruling out the impact of the removal of that many whales. I just couldn't believe that the loss of that much krill-eating biomass didn't have some affect on the ecology of the animals I was studying. In a sense, Emslie and Patterson's work vindicates my uneasiness. They noted that the switch from fish to krill coincided with the presumed krill surplus and supports the krill surplus theory. They also noted the proponderance of krill in the modern diet of Adelie Penguins is relatively recent phenomenon.

Although this work does support a switch in diet from fish to krill and suggests that the krill surplus may be responsible for this shift, it does not address the fundamental premise in either the krill surplus or sea ice theories for changes in penguin population- that there was a change in penguin populations as a result of the shift from fish to krill.

I believe that all of these factors have impacted penguin populations in one way or another. The physical environment and changes in sea ice extent do have an impact on penguin populations through the availablity of krill to both adult and recently fledged penguins and they affect species differently depending on their dependence on the sea ice environment. I also believe that there was a profound affect on penguins and other Antarctic animals as a result of the loss of the Antarctic Fur Seals and great whales. These factors have interacted and continue to interact in subtle and dramatic ways to influence the distribution and abundance of Antarctic and Sub-Antarctic penguins today.

Steven D. Emslie and William P. Patterson. 2007. Abrupt recent shift in δ13C and δ15N values in Adélie penguin eggshell in Antarctica. Proceedings of the National Academy of Sciences 104(28)pp 11666-11669.

William R. Fraser, Wayne Z. Trivelpiece, David G. Ainley, and Susan G. Trivelpiece. 1991. Increases in Antarctic penguin populations: reduced competition with whales or a loss of sea ice due to environmental warming? Polar Biology 11:525-531

Adelie Penguin colonies from the air. Note the nice pink color of the colonies. Photo by Ron Naveen (Oceanites).

This is where the color comes from - lots and lots of penguins in one spot all digesting large amounts of krill and depositing the remains.

Over many years this forms a layer of ornithogenic soil (old bird shit). Within this layer are old egg shells and concentrated organic pollutants - see here.

Two new books

The first book is one that I have been looking for for my boys since late last year. It is Fidget's Freedom, a children's book written by Stacey Patterson and illustrated by the excellent wildlife artist Vadim Gorbotov (here and here) with a dust jacket endorsement from Steve Bodio. I found it at the San Pedro House visitors center at the San Pedro Riparian National Conservation Area. It is a relatively simple story of a young Peregrine Falcon being reintroduced into the wild as part of the Peregrine Fund's very successful conservation success story concerning the recovery of the Peregrine Falcon in the United States. The illustrations are superb depictions of birds of prey from someone intimate with these animals. Vadim has obviously spent a lot of time observing wildlife and knows how to transfer those observations into art. It has become one of Benton's favorites and one that I don't tire of reading to him either. The next book in the series of three will be titled Fidget's Folly and illustrations for the book can be found here.
An example of Vadim Gorbatov's work

During my travels home from Arizona my plane out of Tucson was delayed about an hour causing me to miss my connection in Denver by a few minutes. I had to wait nearly four hours for the next plane to Billings. This wasn't all bad. I have made very little time for reading for myself lately, and the missed connection provided me the perfect opportunity to indulge in a good book. I had seen a book on whales and whaling in the airport bookstore during my layover on my way south, but upon entering the bookstore this time I realized I was in the mood for some good fiction. As I maneuvered my bags through the narrow aisles and dodge fellow bag-laden travelers, I noticed The Road perched on an overstock shelf above me. I was familiar with Cormac McCarthy's writing after being introduced to his work by Steve Bodio a number of years ago, and I was familiar with the gist of this story, but felt it might hit close to home for me with my young boys at home. I nearly passed it up. I am glad I didn't. I was right though, it did hit really close to home.
It is a story of a father and son journey through a future world devastated by an unnamed disaster that introduced enough dust into the atmosphere to effectively stop photosynthesis. The world that the father and son traverse seven or eight years after the event is harrowing, frightful, and all too possible. I was reminded of the post Katrina events on the Gulf Coast and how rapidly society degenerated into a free-for-all. I was also forcefully reminded of our dependence on sunlight and photosynthesis through the foreboding world McCarthy so simply, yet powerfully, described. The lack of animals of any sort, other than humans, was disturbing (I have no desire to go to the South Pole for the very same reason). McCarthy also pegged the relationship between a father and a young son. That was the hardest part of the book for me. He captured so well the terms of a relationship I am in the middle of right now that it made the book even more real and frightening for me. It still haunts me.

Monday, August 6, 2007

Back to Montana

Fort Peck, MT - I am back in Montana and back to work in the office. My time in Arizona was great and humbling. The bird monitoring course I took was taught by some very good birders - did you hear that chip note? It sounded more cheep than chip so it is species x. I knew about 3 species each morning and the rest were all new. It was quite frustrating but I certainly learned a number of new species and it was really good practice. I would need at least a week in that area to feel even moderately comfortable doing any sort of survey where I would rely on my ability to ID birds by sounds. Other aspects of the course included survey design and data analysis. These sections were excellent and I wish I would have had the instructor for any of my introductory stats courses or even my grad level grad courses. Here are a few more photos from my time in Arizona.

Canyon Towhee

Canyon Towhee

Curve-billed Thrasher

Desert Grassland Whiptail

White-eared Hummingbird (best I could do).

Two-tailed Tiger Swallowtails

Sycamore Bark

Pyrrhuloxia male

Pyrrhuloxia female

California Sister

I can't remember what we wound up calling this one.

Lucifer Hummingbird. This is probably my favorite species of the trip. This was one of those instances when I could have used a bit more light or a tripod or an image stabilized lens. The female was quite pretty too with a really nice buff collar. I wish I could have gotten a photo of her too.

Friday, August 3, 2007

More Arizona photos

Arizona Ridge-nosed Rattlesnake
Immature Yellow-eyed Junco
Anna's Hummingbird building a nest
Elegant Trogon
Red-faced Warbler
Another one
And another
My favorite

Thursday, August 2, 2007

More Arizona bird photos

Common Ground-dove
Common Ground-dove
Gila Woodpecker
Blue Grosbeak
Blue Grosbeak

Rufous-crowned Sparrow
Rufous-crowned Sparrow
Vermillion Flycatcher
Vermillion Flycatcher (female)