HOME: www.hiltonpond.org

GENERAL INFO

CONTENTS

RESEARCH

EDUCATION

PUBLICATIONS

MISCELLANY

2004 BIRD BANDING TOTALS:
BETTER THAN AVERAGE AND
A FEW RECORD HIGHS

After a disappointing 2003 at Hilton Pond Center--a mere 1,189 birds were banded last year--we managed to rebound in 2004 but barely squeaked over the 2,000 mark; a Northern Cardinal trapped on Christmas morning was the year's final bird and brought our total number to 2,002. The fact that we didn't catch any birds after that date was reflective of our banding efforts in 2004; we had one of our busiest travel years ever, including out-of-state trips for Hummingbird Mornings, education and professional conferences, in-school visits, teacher workshops, and GLOBE-related meetings, and then we left early on 26 December for our long-awaited 16-day excursion to study Ruby-throated Hummingbirds in Guanacaste Province, Costa Rica. (More next week about what we found.) Despite these absences--and having to deal with recovering from retinal surgeries in the big migration months of May and October--we still set or tied records of individual birds banded for five species, and we had average or above-average numbers for 15 more. In fact, because we've averaged 1,970 birds annually over the past 23 years, our 2004 total of 2,002 was also above average.

All text, tables & photos © Hilton Pond Center

For us, the highlight of the year was probably the 210 Ruby-throated Hummingbirds banded between 9 April and 28 September--finally taking us over the 200-bird mark for our favorite summer study species. A young female hummer netted on 3 September became our 45,000th bird banded at the Center, and another one 15 days later was our 3,000th ruby-throat since we started studying them in 1984.

This year we also netted a new banding species for Hilton Pond when an aggressive hatch-year male Cooper's Hawk (above) barrelled into a net on 20 November; it was our 124th species banded locally since 1982. (We've also observed another 43 species on or over the property during that span.) On 18 December an adult male Red-winged Blackbird in pristine winter plumage (below) was the 69th species banded for 2004, somewhat less than our 23-year average of 71.2; interestingly, it was also only our 22nd red-wing captured since 1982, when we banded five of them during that start-up year.

The biggest surprise of the year-just-completed was a massive influx of Purple Finches that actually began on 5 December 2003. From that date through 16 April 2004 we banded 1,056 Purple Finches--nearly DOUBLING our single-winter record of 685 set in 1986-87! The 950 PUFIs banded in 2004 also shattered the old calendar-year mark of 697 established back in 1987. In all, Purple Finches made up 47% of all birds banded this year at Hilton Pond; totals for PUFIs stand at 6,736--a species total exceeded only by our 7,003 House Finches.

Two other species eclipsed or tied annual totals in 2004. A Tufted Titmouse on 2 December brought the yearly total to 26 (old record 24), and two Winter Wrens netted three hours apart on 20 October tied the old annual record set last year. (We've only banded ten of this diminutive species in 23 years.)

We captured alarmingly low numbers of several resident birds: 39 Northern Cardinals were 'way under their 23-year average of 79, as were ten Eastern Towhees (avg. 28) and seven Brown Thrashers (average. 20). Our 42 Dark-eyed Juncos (above)--which occur here only in winter--surpassed their average of 29, making us wonder if year-round resident birds that are primarily ground feeders are being targeted by low-flying mosquitoes that transmit West Nile Virus. This year's 13 Gray Catbirds--summer residents that feed on the ground and in the shrub layer--were also down from their average of 38, but our 87 Chipping Sparrows (another winter ground feeder) were up significantly from an average of 56. Conversely, this year's 33 wintering White-throated Sparrows dropped well below their average of 75.

After the glory years of 1991 through 1993--when we averaged almost 660 House Finches annually--numbers have continued to drop; we banded only 181 of this species in 2004. We suspect that HOFIs, whose breeding range expanded dramatically across the southeastern U.S. in the late 1980's, eventually were affected by a population crash due in part to highly contagious conjunctivitis. However, we have no idea what's happened to the many Yellow-rumped Warblers we used to net (immature at left), or whither went those Pine Siskins that so commonly entered winter traps.

Low numbers for some bird species this year at Hilton Pond were undoubtedly due to our being away from the site so frequently, but changing local habitat also may be having an effect. Vegetational succession in former old fields has created a new subcanopy of trees that makes baited traps beneath them harder to find, and birds that formerly hung around in the shrub layer--Common Yellowthroats and other wood warblers, for example--may now simply fly over our ten-foot-tall mist nets as they forage higher up. Nonetheless, we believe our work shows the number of local birds is in decline, perhaps due to loss of habitat in the rest of the neighborhood or on breeding or wintering grounds at other ends of their migrational paths.

Even though it's hard to pinpoint the causes, our numbers indicate there are fewer birds around Hilton Pond than when we started banding in 1982. If accurate, that conclusion is sad, but it shows the value of long-term banding projects such as the one we've conducted more or less continuously at Hilton Pond Center for 23 years. Without such on-going investigations it's REALLY hard to accurately evaulate increases and decreases in populations.

We encourage you to examine the chart and table below to draw your own conclusions about our numbers, and to compare our banding results to what you observe about free-flying birds in your own backyard. We suspect you, too, will conclude that most local bird species are in decline, so we hope in 2005 you'll do what you can to protect and create bird habitat that could help stop the downward slide.

Click HERE for a larger version of the above chart.

* Individuals have been netted but not banded, per federal Bird Banding Lab guidelines for game birds.

Comments or questions about this week's installment?
Please send an E-mail message to INFO.

SPECIES BANDED THIS WEEK:
American Goldfinch--5
Carolina Chickadee--1
Dark-eyed Junco--2
House Finch--5
Purple Finch--1
Northern Cardinal--4
Blue Jay--1

* = New species for 2004

WEEKLY BANDING TOTAL
7 species
19 individuals

YEARLY BANDING TOTAL (2004)
69 species
2,002 individuals

BANDING GRAND TOTAL
(since 28 June 1982)
124 species
45,307 individuals

All text, tables & photos ©
Hilton Pond Center

NOTABLE RECAPTURES THIS WEEK
(with original banding date, sex, and current age)