Friday, November 6, 2009

Mexico, an Elder Statesman

Mexico's wintertime, indoor space

One of the responsibilities that we have is providing the best possible care for our educational ambassadors. This includes being aware of any special care requirements for a particular species as well as the idiosyncracies of the different individuals. Such is the case with our elderly Mississippi Kite, whom we call Mexico, so named because the entire population flies south to Mexico, Central and South America for the winter. Mississippi Kites are insectivores that forage aerially for moths, grasshoppers, cicadas, flying ants and more. As the insects decline with the onset of cooler temperatures, so does the kite population. Mexico, already wearing adult plumage, arrived in 2000. This means that he is at least 11 years old now, the upper limit of a life span of a wild Mississippi Kite. He is not equipped to winter outdoors. During the fall as nighttime temperatures drop, he is only outside during mid-day, and by November he is a permanent indoor resident. However, he seems to take it all in stride and easily transitions to his indoor environment near a sunny window with several perches, a water pan, and food stump. In fact, he seems so comfortable that he spends much of the winter months courting his human companion and artfully arranging towels and stuffed toys in a nestful sort of way.

Wednesday, October 7, 2009

Songbirds and Russian Olive Berries

Cedar Waxwings feeding on Russian olive berries
Yellow-rumped Warbler feeding on Russian olive berries

Currently, we are categorizing the berry production on selected Russian olive (exotic vegetation) and New Mexico olive (native vegetation) plants located on transects in our middle Rio Grande study area. The berries of these two plants provide an important food source for wintering (and to a lesser extend, migrating) birds that frequent the middle Rio Grande bosque. Russian olive berries are particularly important to wintering birds because they remain a viable food source throughout the winter or until the resource is depleted. In contrast, New Mexico berries tend to desiccate as winter progresses, and become a decreasingly useful food source. To date, we have documented over 30 bird species foraging on Russian olive berries, and a similar number exploiting New Mexico olive. Ultimately, we hope to generate a long-term berry production data set (10+ years) that can be compared to environmental conditions (i.e. weather patterns, river flow levels, etc.) to gain insight regarding factors that impact berry crop size in the middle Rio Grande bosque. -- written by Trevor Fetz, avian biologist

Monday, October 5, 2009

Raptors of the Rio Grande Gorge

This Golden Eagle nestling fledged prematurely. However, it still has a good chance of survival because of its large size, and because its parents will continue to provide care while it is on the ground.
Golden Eagles continue to add to existing nests for many years, eventually amassing a massive structure several feet tall and several feet wide.

There is a fissure, a crack of basalt that runs through north central New Mexico. In it lies a river, the hydrologic aorta of the state, the Rio Grande. Within this canyon nesting Golden Eagles thrive, along with Prairie Falcons, and Red-tailed Hawks. Commonly known as the Rio Grande Gorge, it contains some of the largest Golden Eagle nests that I have ever seen. Some of which attain heights nearing 10 feet, attesting to fact that Golden Eagles have been using these nest sites in the gorge for a very, very, long time.

Written by Ron Kellermueller, raptor biologist

Wednesday, August 26, 2009

Fall Songbird Migration - Albuquerque Bosque

MacGillivray's Warbler. Photo by Doug Brown.

Fall migration is now clearly in full swing. Large numbers of MacGillivray’s Warbler, Yellow Warbler, and Virginia’s Warbler are currently moving through the bosque. Wilson’s Warbler numbers are currently comparable to those of the three warblers mentioned above, but are small compared to the numbers that will be present in the bosque during the coming weeks. Orange-crown Warbler and Townsend’s Warbler are also moving through in relatively large numbers. Western Wood-Pewee numbers have greatly increased this week compared to earlier in the month. We undoubtedly undercount vireos in the bosque because they rarely vocalize during this time of year, but we have recorded three species so far this week. Warbling Vireos are regular right now, and we finally detected our first Plumbeous Vireos this week. Most exciting, however, is the detection of three Red-eyed Vireos over the past eight days, a species that is normally very rare in the bosque.

Monday, August 10, 2009

Songbird Migration Is On!

Yellow Warbler. Photo by David Powell.

Migration is beginning to pick up steam in the bosque. Among warblers, Yellow Warblers are currently moving through in the largest numbers, with smaller numbers of MacGillivray’s Warblers and Virginia’s Warblers also popping up. Wilson’s Warblers are just starting to trickle into the bosque, and we have also recorded Black-throated Gray Warbler and Orange-crowned Warbler over the past week. Other migrants currently moving through include Western Tanager, Warbling Vireo, Rufous Hummingbird, Broad-tailed Hummingbird, Calliope Hummingbird, and Gray Flycatcher. Other species of note include Lark Sparrow and Chipping Sparrow, both of which are moving around in large numbers, the occasional Red-breasted Nuthatch, and increasing numbers of Bullock’s Oriole and Lazuli Bunting

Wednesday, August 5, 2009

Golden Eagle Nestlings

These Golden Eagle nestlings were filmed through a spotting scope by Hawks Aloft raptor biologist, Ron Kellermueller. The parents had just made a prey delivery as Ron and his son, Malcolm watched. Check out the size of this nest!