Caribbean National Forest, Puerto Rico
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Of in the 15 participating banding stations in Region Park V in the autumn of 1983, only Baltimore's Leakin Park was new. Two others that were active but not reported in 1982 rejoined us in 1983. Four of the 15 stations are home operations, 2 are on Federal land, 2 in city parks, 2 at private schools, 2 at coastal concentration spots, 1 on a wildlife sanctuary, 1 in an abandoned orchard, and 1 in an impending real estate development. Coverage and catch characteristics of each station are summarized in Table 1 and in the pie charts that accompany the station reports. The habitats sampled vary so much among stations that species and even family composition are unique at each site.
North American Breeding Bird Survey data for the period 1966-1987 indicate that Eastern Bluebird (Sialia sialis) populations declined during the 1970s, primarily in association with either severe winters or severe spring storms. In recent years, bluebird populations have increased to levels similar to those observed during the first year (1966) of the survey. Survey results suggest that climate has an important role in affecting short-term population declines in bluebirds.
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The North American Breeding Bird Survey monitors changes in bird populations through time using annual counts at fixed survey sites. The usual method of estimating trends has been to use the logarithm of the counts in a regression analysis. It is contended that this procedure is reasonably satisfactory for more abundant species, but produces biased estimates for less abundant species. An alternative estimation procedure based on estimating equations is presented.
We applied mark-resight and area-conversion methods to estimate deer abundance at a 2,862-ha area in and surrounding the Gettysburg National Military Park and Eisenhower National Historic Site during 1987-1991. One observer in each of 11 compartments counted marked and unmarked deer during 65-75 minutes at dusk during 3 counts in each of April and November. Use of radio-collars and vinyl collars provided a complete inventory of marked deer in the population prior to the counts. We sighted 54% of the marked deer during April 1987 and 1988, and 43% of the marked deer during November 1987 and 1988. Mean number of deer counted increased from 427 in April 1987 to 582 in April 1991, and increased from 467 in November 1987 to 662 in November 1990. Herd size during April, based on the mark-resight method, increased from approximately 700-1,400 from 1987-1991, whereas the estimates for November indicated an increase from 983 for 1987 to 1,592 for 1990. Given the large proportion of open area and the extensive road system throughout the study area, we concluded that the sighting probability for marked and unmarked deer was fairly similar. We believe that the mark-resight method was better suited to our study than the area-conversion method because deer were not evenly distributed between areas suitable and unsuitable for sighting within open and forested areas. The assumption of equal distribution is required by the area-conversion method. Deer marked for the mark-resight method also helped reduce double counting during the dusk surveys.
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Mery (1966) showed an almost equal sex ratio, males returned more frequently than females, over 50% of returns paired with other returns, an adult return rate of 20%, and no pair bonds maintained for more than one season. Her study lasted 13 years. Our study has shown that the return rate of locals to parent colonies is 4.1%, sex ratios are nearly equal (combination of banding and observation), return rate of locals to nearby colonies is 0.9,one pair maintained the pair bond for two years, SY females lay fewer eggs than ASY's, SY adults occasionally do not feed frequently enough to maintain the normal growth pattern of the young, SY adults often build poorly constructed nests with little or no mud, overall nest success is lower in SY adults, adults do indeed return to the same colony (19.6%) box and/or compartment, sexes are balanced in a stable colony, males or females are sometimes in excess in a new colony, SY adults are predominate in a new colony, the limiting factor in colony size is most likely the number of boxes and/or compartments available for nesting and,finally, adults and young do indeed use the boxes for roosting after nesting and fledging is complete (even boxes not their own). All of our results are tentative and subject to change after f rther study. Much additional study will be required before we can come up with conclusive answers to many of these questions about the Purple Martin.
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A first-winter Ovenbird (Seiurus aurocapillus) banded in a cacao plantation in central Belize on 8 February 1989 was found dead on the deck of a home on its breeding ground in northwestern Pennsylvania on 28 June 1997, tying the 9-year age record for the species.
The Hollywood, Butler Island, and Wekiva Basin stations did not operate this year, but we welcome back Jekyll Island, GA, with its flagship species, Western Palm Warbler (835); and we are glad to have a report from Rock Springs Run State Reserve in Florida to replace the Wekiva Station. Except for a couple of good rains in August, the second half of the year was droughty in Maryland and Virginia, while Florida had a surplus of rain throughout the autumn. Baltimore recorded its driest fall since 1941. The 2001 stream inflow entering Chesapeake Bay was 36 percent below normal, securing the status of the region's longest running drought since the 1960s. Part of the extended drought can be blamed on two consecutive years without a hurricane making landfall in continental United States--the first time in two decades that this had happened. September and October averaged cooler than normal throughout the region, but the other months had excessive heat. The stations that opened in early August detected little movement in the first half of the .month. States to the north of us were experiencing record-breaking heat, culminating in the hottest day in the past quarter century in New York City (104 ° F) on 9 Aug. On the following day he temperature 40 feet below the surface of Lake Erie more than three miles off Cleveland reached 80 ° F for the first time in history.
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July, August, and September were cool and wet in the Southeast, with multiple hurricanes threatening the banding stations. Banding results ranged from poor in Laurel and Chincoteague to excellent at Chino Farms, Kiptopeke, Jekyll Island, and the Florida stations. There was little agreement on peak migration days, which ranged from 11 Oct to 6 Nov. Likewise, the date for maximum species ranged from 19 Sep to 9 Oct in Maryland and from 11 Sep to 15 Oct in states farther south. Myrtle Warbler numbers are still below normal, and warblers in general seemed scarcer except at Bill Baggs Cape Florida where warbler numbers approached those at Appalachian stations. Jekyll Island had an extraordinary total of 69 Tennessee Warblers in October, possibly pushed off course by the remnants of Hurricane Matthew in the lower Mississippi valley. Vireos are seldom mentioned in Region IV reports, but this year Blue-headed Vireo was a first for Eden Mill and was a highlight at Jug Bay. Chino Farms banded a record eight Warbling Vireos, Kiptopeke banded a Yellow-throated Vireo and the first Warbling Vireo in at least 11 years. Jekyll Island banders had two Philadelphia Vireos. Finally, Michelle Davis's report from Bill Baggs Cape Florida State Park concludes with the mention of three West Indian vagrants.
This paper presents the current breeding range of Painted Bunting (Passerina ciris) in a series of maps and a narrative, in particular that of the eastern population, which is restricted to the states of North Carolina, South Carolina, Georgia, and Florida. Some conservation measures are recommended to protect this population. In light of the extensive habitat loss in the Outer Coastal Plain of these states, which comprise the areas of the population's greatest density, it is imperative that a consortium of diverse interests work together to provide sufficient habitats for this colorful native songbird.
We applied mark-resight and area-conversion methods to estimate deer abundance at a 2,862-ha area in and surrounding the Gettysburg National Military Park and Eisenhower National Historic Site during 1987-1991. One observer in each of 11 compartments counted marked and unmarked deer during 65-75 minutes at dusk during 3 counts in each of April and November. Use of radio-collars and vinyl collars provided a complete inventory of marked deer in the population prior to the counts. We sighted 54% of the marked deer during April 1987 and 1988, and 43% of the marked deer during November 1987 and 1988. Mean number of deer counted increased from 427 in April 1987 to 582 in April 1991, and increased from 467 in November 1987 to 662 in November 1990. Herd size during April, based on the mark-resight method, increased from approximately 700-1,400 from 1987-1991, whereas the estimates for November indicated an increase from 983 for 1987 to 1,592 for 1990. Given the large proportion of open area and the extensive road system throughout the study area, we concluded that the sighting probability for marked and unmarked deer was fairly similar. We believe that the mark-resight method was better suited to our study than the area-conversion method because deer were not evenly distributed between areas suitable and unsuitable for sighting within open and forested areas. The assumption of equal distribution is required by the area-conversion method. Deer marked for the mark-resight method also helped reduce double counting during the dusk surveys.