Green grass and brown trees

A week has passed since our arrival on Catalina. Jongmin and I took the 1 hr long ferry ride from San Pedro to Avalon last Friday, taking advantage of the excellent weather and opting for the roof-top view of the surrounding ocean. The trip was much different than our last ride on the Catalina Express. This time, we were surrounded by tourists destined for Avalon at the start of the long weekend. Last time, we were surrounded by firefighters returning to the mainland after the so-called "Island Fire."

That was May 2007. The island was a parched landscape that had been suffering from the most severe drought on record, and 4,760 acres of the island's interior had just burned with the boundary extending right up to the city of Avalon. We were in the interior of the island for the duration of the fire, without power or contact with the outside world. Helicopters flew over our heads constantly as they made loops between the fire on the horizon and the reservoir in our backyard. The fire burned for a few days and when it was out we left the island, cutting short our field season by one week.

This year, upon our arrival in Avalon, we were pleased to find an island much greener than when we last saw it. There was grass, green grass, the oaks on the surrounding hillsides had grown new leaves and many of the flowers had started to appear. The island received several inches of rain in January and February and it showed. We were ecstatic. The breeding season would soon be upon us, or so we thought.

We retrieved our vehicle, left for us by the Catalina Island Conservancy, made a brief stop at the local grocery store, and set off on our journey into the island's interior. The drive took us through the Island Fire, the road still lined with eucalyptus trees but the surrounding oaks covered in fire-scars. Shortly thereafter we found ourselves in Middle Ranch and settled into what is called "the bunkhouse," a place we share with the Conservancy's field technicians.

The next morning we awoke before dawn for our first day of fieldwork. Our expectations heightened by the ever-present greenery, we were shocked when we drove into the canyon where our field site is located to find it looking even browner than when we left. The understory was a brilliant colour of green, but that stood in stark contrast to the canopy, which was an ugly colour of brown. The oaks had dropped their old leaves and most hadn't grown new ones. It was puzzling. How could they be so green on the rest of the island, and yet so brown on our study site?

Despite the rather sad looking trees, we were pleased to find many of our banded birds waiting for us on the same territories they held the previous year. Red-Aluminum-Red-Red, check. Aluminum-Blue-Orange-White, check. Aluminum-Red-Green-Red, check. We counted over 20 banded birds on the first day alone, and many more birds who have yet to be banded. The birds were back, but we had a sinking feeling that the breeding season would be weeks away. Few males seemed to have acquired females, and food didn't seem particularly abundant given the sparse foliage. Our continued surveys over the course of this week have only served to strengthen that suspicion - and so we wait.

Goodbye Colorado, Hello California

Winter is no more, at least for me - a rather odd thing for a Canadian to say in early February. The last snow to fall on my shoulders came last weekend when Jongmin and I were driving through Utah en route from Colorado to California. The snow quickly disappeared as we descended into Arizona, at around the same time that the conifers of the Rockies gave way to the palm trees of the southwest. Shortly thereafter we were in an even warmer California, our home for the next three months.

Our destination was not Catalina Island - rather, we made our way to Ventura, just north of LA, to attend the 7th California Island Symposium. The meeting took place from February 5th to the 7th and brought together folks who study pretty much anything on islands off the coast of California and Baja Mexico, from ecologists to geologists to archaeologists. There were representatives from universities across the United States and Mexico, numerous government agencies, and NGOs such as the Nature Conservancy and the Catalina Island Conservancy. Over 400 presentations shed light on ecosystems of the past and present, as well as management techniques and challenges specific to the region's many islands.

The sexy bird that it is, there were enough talks on orange-crowned warblers to fill much of the session on terrestrial birds, and yet another poster describing the project's work on Catalina Island:

Scott Sillett, "Annual survival of orange-crowned warblers breeding on Santa Catalina Island" (talk)

Helen Sofaer, "The effects of island scrub-jays on orange-crowned warbler reproductive behavior and nest success" (talk)

Jongmin Yoon, "Habitat modeling for orange-crowned warblers breeding on Santa Catalina Island" (talk)

Katie Langin, "To breed or not to breed? Demographic consequences of the driest winter on record for songbirds on Catalina and Santa Cruz Islands" (talk)

Hannah Montag, "Nest site selection in the Catalina Island orange-crowned warbler (Vermivora celata sordida)" (poster)

Hearing about research on the Channel Islands and seeing familiar faces has given us an extra spark of excitement as we head into the 2008 field season. On February 15th we will take the ferry from San Pedro to Catalina Island and commence our 5-month stint in the field. In the meantime, we are enjoying our final days of sleeping in past the crack of dawn.

The warbler with the orange crown

With a name that includes a bright colour like 'orange' and an ornamental description like 'crown', one might be under the impression that orange-crowned warblers are dazzling little creatures. That impression would be wrong. In fact, the orange crown is barely perceptible unless you see a male puffing up his crown in an aggressive display or you blow on his crown feathers while you hold him in your hand. Some have even gone so far as to label this little songbird the drabbest of all the warblers in North America.

Despite its lack of showy plumage, the orange-crowned warbler is a fascinating bird to study. It is one of the most widely distributed warblers in North America, able to inhabit conditions as diverse as the arid, Mediterranean climate of southern California and the sub-arctic, highly seasonal environment of Alaska and northern Canada. It also exhibits diverse migratory strategies. For instance, the subspecies we study in the southern portion of its breeding range is a year-round resident of southern California, while the northern subspecies migrates all the way to the Gulf coast to over-winter. Such differences in breeding locale and migratory strategy translate into marked differences in life history, as southern breeders have low fecundity and high survival while northern breeders have high fecundity and low survival. We ecologists classify these populations as falling at the 'slow' and 'fast' end of the life-history continuum, respectively, classifications that carry with them a whole suite of additional traits. Our primary research aim is to identify the causes and consequences of life-history diversification among populations of orange-crowned warblers.

So how do we do this? Well, 'unfortunately' this requires that nearly half our year be spent in the wilds of California and Alaska, a price we are willing to pay in the name of research. With our trusty field assistants in tow, we record the locations of territorial individuals, capture and band them for individual identification, and follow their breeding activities over the course of the season. We find nests, videotape them to observe parental activity, and when the nestlings are old enough we take them out for a brief period of time to band and measure them. The populations we study have non-overlapping breeding seasons, so we are able to spend February, March, and April in California and May, June, and July in Alaska. Stay tuned as our fieldwork gets underway and we to peer into the lives of these cryptic warblers.

Blog Intro

Hello! I am a PhD student in the Graduate Degree Program in Ecology at Colorado State University, about to embark on the first field season of my doctoral research. Over the next 6 months I will be traveling to Catalina Island, part of the Channel Islands off the southern coast of California, and to Fairbanks in central Alaska to study a small songbird called (you guessed it!) the orange-crowned warbler. The goal of my research is to examine the role of climate in shaping the demography and life history of these warblers, part of a larger project initiated in 2003 by my advisors, Drs. Cameron Ghalambor (CSU) and Scott Sillett (Smithsonian Migratory Bird Center). I will be working with fellow grad students Jongmin Yoon and Helen Sofaer, as well as a team of field assistants with a avid interest in bird ecology. The purpose of this blog is to chronicle our on-going field research as we follow the breeding activities of this widely distributed warbler, first in California and later in Alaska. I hope you will join us.