Project Osprey Watch
Citizen Scientists Tracking the Vineyard Ospreys
Newsletter #1 - Spring 1999
The Ospreys are Coming!
Ospreys are making their way up the coast and have reached my latitude
down here in North Carolina. They should be arriving on the Vineyard any day now. With a
bit of luck, I may get this newsletter out to our fearless team of Osprey spotters before
the first birds hit the Island. But then again, I'll probably waste so much time fooling
around with the publication software that the first males will beat me to the punch.
What is Project Osprey Watch?
Project Osprey Watch is an effort to monitor the Osprey population on
Martha's Vineyard. Because there are so many nests scattered around the island (and
because the Project coordinator, Rob Bierregaard, is based in North Carolina), we are
enlisting the help of osprey afficianados to track the breeding success of the Vineyard
Ospreys.
Why study the Vineyard Ospreys?
Until the early 1990s, Gus Ben David was able to keep track of all the
pairs on the Island. After about 1992, Gus just got too busy to follow all the nests.
Shortly thereafter, Gus and many others noted that many of the Vineyard Ospreys were
having trouble reproducing and the historically high fledging rates we enjoyed on the
Island fell precipitously, with young starving and many historically productive nests
failing to produce any young year after year.
Project Osprey Watch will help us find out how many pairs of Ospreys
are on the Island. We'll learn if the birds are still having trouble raising young and if
so, if this an island-wide or localized phenomenon.
Citizen Scientists
A growing number of professional ornithologists are eliciting the aid
of amateurs to collect data that would be impossible to obtain otherwise. Important
scientific papers are being published thanks to the efforts of such "citizen
scientists." Thanks to all the spotters who helped us track the birds through the
1998 nesting season, we know more about the Vineyard population than we have in almost a
decade and have begun a first-rate study of the Vineyard Osprey population. Let's keep it
going!
The 1998 Season in Review
1998 was a productive year for the Vineyard Ospreys. Over Memorial Day
weekend last year I visited all 111 nest poles on the Island and confirmed 65 nesting
pairs. This is down from the peak of over 70 pairs in the early 90s, but 64 pairs more
than were on the Vineyard when I climbed into my first osprey nest at Mink Meadows in
1969! 54 young were fledged out of the 50 nests (successes and failures) for which we have
data. This is an average of over 1 young per active nest and safely over the break-even
rate of 0.88 young per nest needed for an Osprey population to remain stable. So, if our
birds continue to produce young at this rate, we should see the population hold its own or
even begin to increase.
Nests started: 65
Successful nests: 33
Failures:
17
Data pending: 8
No data:
7
Getting Involved
We are missing data from a number of nests that were in out-of-the-way
corners of the Island where we were unable to find someone to watch them last season. We
hope that by including more Osprey watchers this year, we will be able to get better
coverage of more nests. Even if you don't have a nest on your property, you can help if
you can regularly visit one or more nests. The map below shows (with question marks) the
nests that we missed last year. There may be some changes in 1999, but we're sure to have
some nests that we'll need help with. We will post the 1999 map on this web site in
mid-June. Contact Rob Bierregaard if you are interested in helping out with some of these
nests.
A History of Ospreys on Martha's Vineyard
While no accurate records exist, there were probably never more than
five to ten pairs in the 1900s through 1969, when our studies began. Most nests that are
remembered were in old pines left from extensive fires in the 1930s and 1940s.
Two pairs of Ospreys nested during the late 1960s. Beginning in 1969
artificial nest platforms were provided, originally for the traditional pairs whose nests
in dead pine trees were lost in winter storms and later as new pairs were discovered
attempting to build nests on power transformers. (Veteran line crews remember knocking
Osprey nests off of power poles as far back as the 1950s!)
Since 1969, 114 nest poles have been erected, and the Vineyard Osprey
population increased to a peak of at least 65 (probably more than 70) pairs in 1992.
The population increased exponentially from 1975 through 1990, more
than doubling every five years. Productivity during this time averaged 1.84 young fledged
per breeding pair.
Beginning in 1992, we noticed a dramatic decline in the number of young fledged.
Observations of Osprey's hunting and breeding behavior indicated an
island-wide collapse of the Ospreys' prey base.
1999
In early June, Rob Bierregaard will come to the Vineyard to canvas all
the nest poles. We will contact landowners if we have any new nests and hope to enlist the
help of some volunteers to follow some of the remote nests. Rob will then reluctantly
retreat to the heat of North Carolina and collate the information from the lucky souls who
get to spend the summer on the Island.
Tips for Osprey Watching in 1999
I think everyone I spoke to expressed an interest in continuing to
participate in the Osprey survey, so here's what you can do to make our data even more
valuable this year:
1. Record your observations in a journal or diary.
2. Make your observations at least weekly, and take notes as soon as
you see ANY interesting behavior. Don't tell yourself you'll write it down later - you're
almost sure to forget some interesting details that might prove useful.
3. Note the dates you first see the parents around the nest and, later
in the spring, feeding their young.
4. Did more than two birds squabble over the nest"?
5. Watch carefully to see how many heads are popping up when Dad
brings home a fish-especially just after hatching.
6. Volunteer to make regular visits to one of the
nests that we missed last year. If you live near any of the nests marked on the map below
with a "?" and want to follow their progress, I will let you know exactly where
the nest is.
7. Pay special attention at fledging time. When the young are ready to
fly, they'll be as big as their parents, so make sure your count of fledglings doesn't
include a parent sitting on the nest with its young.
Contacting "Headquarters"
If you would like to enlist in the Vineyard Corps of Osprey
watchers, have any questions, or want to send us early reports of activity at a nest that
you know of, Rob Bierregaard can be contacted by mail at 2405 Westfield Rd, Charlotte, NC,
28207, or by phone (704 333 2405); fax (704 333 2404); or email: rbierreg@uncc.edu.
Or you can also reach Gus Ben David at Felix Neck, at 627 4850.
Interesting Websites
If you have access to the internet, you might be interested in the
following web sites:
Follow Ospreys via satellite transmitters on their migration to and
from their wintering grounds in South and Central America at the website of The Raptor
Center at the Univ. of Minnesota http://www/raptor.cvm.umn.edu/
Learn more about "Citizen Science" at Cornell: http://www.birdsource.org
Birding and ornithology in general: http://www.nmnh.si.edu/BIRDNET
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