Date: Tue, 3 Apr 2001 01:48:46 +0000 |
From: Nancy L. Newfield colibri@GS.VERIO.NET
Subject: Louisiana Hummingbird Banding - Winter 2000-2001
Louisiana Hummingbird Banding - Winter 2000-2001The following is a summary of the hummingbird banding activities of Dave Patton, Linda Beall, and Nancy Newfield over the course of the 2000-2001 winter season. This project was initiated in 1979 as a means of documenting the numbers and species assortment of hummingbirds that spend the winter months in Louisiana. Traditional wisdom of the 1970s was that any hummers occurring during the winter months were vagrants or they were Ruby-throats that forgot to migrate after the nesting season. At that time, it was thought that nearly all wintering hummers perished to cold weather.
The season, as we define it, begins with the arrival of the first non-Ruby-throated Hummingbird in late summer. Typically, the first arrivals are in August and most are returnees from previous seasons. During the early part of the season, we primarily attempt to verify returning hummers. Later, as several birds stake out territories at a site, we try to capture and band as many as possible. Because the last stage of Ruby-throated southward migration extends well into December, it is difficult to categorize individuals of that species early in the winter banding season. Therefore, we arbitrarily define wintering for this species as those we encounter on or after 15 November, though some of those birds may actually be tardy migrants.
The banding season ends in late February or early March as wintering birds begin leaving and summer resident Ruby-throateds begin arriving. At that time, wintering birds become more difficult to catch and banding trips become less productive, though some wintering birds stay well into April or even early May.
Totals for the 2000-2001 season are:
This total is 2 1/2 times the previous record number [166 individuals of 9 species + 18 returnees & 1 foreign recapture] banded in the 1999-2000 winter season! All three banders are self-employed, allowing some flexibility in scheduling, but none were able to devote more than 2 days per week to the project.
All were banded in the southern third of the state, roughly the area south of the Interstate 10/12 line. Patton covered the area from Baton Rouge westward, while Newfield covered Baton Rouge eastward, excepting St. Tammany Parish, which was primarily covered by Beall. St. Tammany Parish was formerly covered by Newfield. We all banded in Baton Rouge and probably caught only a fraction of the hummers around. The Lafayette area covered by Patton had about the same number of birds as in the previous high season of 1995-1996. Newfield's portion held enough to provide her a personal best. Beall, who recently began banding hummers, established a benchmark to set next year's expectations.
The Louisiana Winter Hummingbird Project differs substantially from passerine migration banding studies. Most sites host only a few hummers, so efforts must be made to catch individuals rather than mist-netting whichever birds might pass through. Most captures are made using cage wire traps placed around a feeder. Mist nets and other types of traps are used occasionally.
We are constantly seeking new and better capture methods. In 1999, John Owens invented a remote electronic trap tripper that enables the bander to trap without being tethered to a monofilament cord. This has enabled us to trap more effectively and while doing other tasks. Often, it is not necessary for us to be outdoors, certainly a welcome comfort in cold weather. Thank you, John! All trapping took place in backyards and gardens typical of the area. Hummers were attracted to nectar-producing plants and feeders. Most hummerhosts garden specifically to attract hummers. At no time were feeders the only source of food.
Almost all birds were color-marked, using a non-toxic acrylic paint on their crowns. Color-marking allowed us to avoid repeatedly capturing the same birds and it permitted hummerhosts to specifically identify each individual. Color-marking enabled the hosts to distinguish lookalikes and to notice new birds as they appeared. In several locations, we found more individuals present than had been tallied by the hosts. In most locations, the roster of individuals did not remain constant. Instead, while a few individuals defended territories throughout the winter, many seemed to be traplining over a fairly large area. This required us to make two or more visits to a number of sites as new birds replaced birds that had already been banded.
Weather can play a significant role in this project. We do not band during subfreezing temperatures or during heavy rain, but neither was a major factor this winter. Dense fog can impede travel, though at no time did it become dense enough to cause us to abandon a planned trip. Only two days of planned banding had to be rescheduled because of heavy rain. Most of the region experienced frost and brief periods of freezing weather during December and January. These episodes reduced flowering of many subtropical plants, making hummers somewhat more dependent on feeders.
The productiveness of individual sites varies from year to year. The Robichaux home in Raceland produced 44 new birds [5 species] and 3 returnees - an all-time high! The previous high for that site was 6 individuals of 2 species. The Sylvest home in Gramercy yielded 25 new birds and 1 returnee. Yet, only a single Rufous was banded at the regularly productive Street home in LaPlace.
Rufous are always the most numerous wintering species in our area. Most years, their numbers comprise slightly more than 50% of the total number of hummers banded. They were especially numerous this winter with the total number banded  almost 3 times the previous high number [87 in 1999-2000] of Rufous banded in a winter season. Their numbers account for more than 60% of the 2000-2001 total. This is all the more interesting in light of this species' "declining" status.
Ruby-throateds have always been rare in winter in Louisiana. This season's total of 61 far exceeds the previous high number of 15! For the first season ever, Ruby-throateds ranked second on order of abundance. However, these birds were not evenly distributed throughout our area. Large numbers of Ruby-throateds seemed to be concentrated in the extreme southeastern part of the state - Thibodaux, Raceland, the River Parishes.
Black-chinned numbers were also up. The 53 individuals banded were significantly more than the previous season's 17. Their numbers seemed to be rather evenly distributed among the various parts of the state covered. In the early years of this project, Black-chinneds outnumbered Ruby-throateds by a factor of four.
Buff-bellied totals  were similar to last year's numbers , but the number of returnees  was twice as many as last year . One probable returnee could not be caught. Considering the small number of Buff-bellieds handled, the percentage of returnees is far higher than the percentage of returnees for any other species.
Calliope first appeared in Louisiana in 1982 and it is still on the state review list, but the 19 banded should give the powers that be cause to examine this bird's status. Last season, 9 were banded.
Broad-billed, Broad-tailed, and Allen's are always rare and this season was no exception. Fewer Broad-tailed and Allen's were banded than last year, though those statistics are probably not significant considering the small percentage of the whole total they represent. No Anna's were definitely reported anywhere in our area.
It was a season of many highlights! In the third week of January, Beall captured a female Black-chinned at her Covington home that had been banded in Pascagoula, Mississippi, by Bob Sargent only a couple of days before. This bird was obviously migrating at a time when hummers are presumed to be resident on their wintering grounds. The distance between the two sites is about 95 miles. It remained only a couple of days.
About two weeks later, at the Sylvest "Winter Hummerland" home in Gramercy, Newfield captured another of Sargent's birds. This time it was a female Rufous that had been banded in Aliceville, Alabama, in late November 2000. This bird had last been seen at its original site 15 days before its recapture. The distance between the two sites is about 320 miles. This bird enjoyed Louisiana hospitality for more than a month before moving on.
Returnees prove winter survival and give us data concerning longevity. One highlight of the season was the 23 July appearance of a banded adult Buff-bellied Hummingbird at the Nowell home in LaPlace, a returnee, which had been an adult when banded in February 1993. Because this individual was an adult when it was banded, we can be sure it was hatched no later than the breeding season of 1991. This bird, nicknamed "Junkyard Dog" because of his irascible demeanor, set the longevity record for its species. He was not captured for verification until 26 February at which time he was nearing 10 years of age. The wily Junkyard Dog was fat and healthy in appearance. He was last seen 1 March.
2 Calliope returnees in the Baton Rouge area doubled the number of returnees recorded in Louisiana for that species. Yards with the proper habitat to attract Calliopes often attract several.
In November 2000, a female Ruby-throated, banded as an immature at the Owens home in Covington in November 1999, was recaptured at the Rudiger home about 4 miles away. All other returnees except 1 were captured at the site where they were banded. After the aforementioned Buff-bellied, the oldest was a female Rufous banded as an immature in the winter of 1995-1996, followed by 6 Rufous banded as immatures during the 1996-1997 winter season. One of these birds had not been recorded during the years since banding despite regular winter banding at that site. Another Rufous returned from the winter of 1998-1999. The remaining returnees had been banded during the 1999-2000 winter season. 1 female Rufous that was banded at a site that is no longer active found a good home about 5 miles away.
A banded adult male Ruby-throated resided at the Nowell home in LaPlace all season, but he evaded capture. He is thought to be an individual that was an adult when banded at the Street home in LaPlace in December 1997. That bird was captured at the Nowell home and at the Street home the previous winter season. These two sites are more than .5 miles apart and several other banded birds have been known to go back and forth between them.
The Louisiana Winter Hummingbird Project has benefitted from the enthusiastic assistance and generosity of numerous people. Many hummerhosts opened their doors at ungodly hours and sustained us with strong coffee, juice, breakfast and lunch. Several maintained a running tally of birds in their cities or towns and set up banding day schedules for us. Others wrangled equipment, trapped birds, and recorded data. We thank James Beck, Laurie Binford, Olga Clifton, Miriam Davey, Les Eastman, Carol Foil, Bill Fontenot, Steve Locke, Beth and Sammy Maniscalco, Charlie Muise, Rose and Jack Must, John and Margaret Owens, Stacy Peterson, Lisa Robichaux, John Sevenair, Gene and Edna Street, Tom and Eloise Sylvest for the many hours they have invested in this project. We appreciate your special help - and we'll be looking for you next season!
Nancy L. Newfield
Metairie, Louisiana USA