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2003 - A
Banner Year for Piping Plovers in Virginia
Considered
to be a true master of camouflage, the piping plover (Charadrius
melodus) is a small, inconspicuous shorebird with a
sand-colored back, narrow black neck ring, white belly, orange
legs and a small orange and black bill. Even its bell-like call
is indiscreet and endearing. In 1986, the US/Canada Atlantic
Coast piping plover breeding population was listed as federally
threatened under provisions of the US Endangered Species Act.
Virginia is part of this population's southern breeding range
and since 1986 has supported a relatively stable number of
nesting pairs (Figure 1). Piping plovers typically nest on
sparsely vegetated ocean-facing beaches, sand flats and washovers. Since the late 1990's, 100% of the breeding activity
in Virginia has occurred on the Eastern Shore's barrier islands.
Many of the barrier islands provide ideal breeding habitat in
the form of wide beaches with extensive wash-over areas that
offer unimpeded access to mudflats, sandflats, tidal shorelines
and other feeding areas where insects, marine worms, and other
terrestrial and aquatic invertebrates are abundant and within
easy reach of hungry plovers.
Every spring,
piping plovers return to their breeding grounds and upon their
arrival, the males attempt to attract mates by performing a
series of complex aerial and ground displays. They also have the
added task of staking out a breeding territory and defending it
against other males. Soon after a pair bond is established
between a male and a receptive female, the female usually lays
four eggs in a shallow scrape made in the sand. Both adults
share incubation duties, which last about 25-28 days. Although
chicks leave the nest within hours after hatching and
immediately begin feeding on their own, their parents watch over
them until they are fully-grown and able to fly. Chicks seek
refuge and warmth under the adults during inclement weather, and
when a potential predator enters the breeding territory one of
the parents will usually perform a broken wing display to lure
it away from the brood. The young are capable of sustained
flight and considered to be full grown or fledged at about 25 –
28 days of age. Soon after the brood has fledged, the birds
disperse to their southern wintering grounds. Plovers typically
begin breeding at one year of age and rear only one brood per
year.
In
2003, an estimated 114 piping plover pairs nested on Virginia's
barrier islands, which represents the seventh highest annual
total recorded in the state since 1986 (Figure 1). Productivity
studies conducted on four major breeding islands this year
revealed the highest fledging success (an average of 1.90 chicks
fledged per pair) ever reported in the Commonwealth (see Figure
2). All sites monitored for productivity in 2003 experienced
substantial increases over the previous year (Table
1), but the most striking improvements occurred on Metompkin
Island (1.68 chicks per pair) and Cedar Island (2.00 chicks per
pair) where past estimates have always hovered around one chick
per pair. The statewide increase in breeding success may have
been attributed, in part, to high prey availability resulting
from significant amounts of rainfall that kept the surfaces of
mudflats and sandflats wet and favorable for invertebrates.
Whatever the reasons were that led to last year's breeding
success, Virginia was one of the few Atlantic coast states that
reported a productivity estimate well above 1.24 chicks per
pair, the minimum value necessary to maintain a stable
population.
Piping
plovers have many natural enemies such as raccoons, foxes,
crows, gulls and other birds and mammals who love to feast on
eggs, chicks and an occasional adult bird. Storms and spring
high tides often wash out a portion of the nests and/or drown
flightless chicks. Humans visiting the barrier islands during
the breeding season may unknowingly take their toll on plovers
as well. Fortunately, people can do a lot to minimize
disturbance to nesting birds. Listed below are a few simple
measures to take when visiting the barrier islands during the
breeding season (April - September):
- Keep
pets at home since they are not allowed on most islands.
Unleashed dogs will often flush incubating adults from their
nests or chase after young birds.
- Always
remain as close to the water's edge as possible. Avoid
wandering over dry beach or vegetated areas (i.e., dune
grass, marsh grass, and scrub/shrub habitats) where birds
might nest and stay away from mudflats where young chicks
and adults actively feed.
- Keep out
of all posted nesting areas and stay at least 100 yards from
any nesting bird or bird colony. People venturing near
nesting sites may cause adult birds to leave the nest
thereby exposing unattended eggs or chicks to predators or
excessive temperatures. People may also inadvertently step
on well-camouflaged eggs or chicks.
- Always
pay attention to the birds around you. The birds will let
you know if you are too close by vocalizing, taking flight,
and/or exhibiting defensive behaviors.
- Avoid
disruptive activities such as camping, campfires, fireworks,
kite-flying and loud parties. These activities are generally
not allowed on any of the islands.
- Take all
trash with you when you leave the islands.
Note that
many of the barrier islands are closed to the public either year
round or during the breeding season. If you have questions
regarding island closures or wish to learn more about piping
plovers please call The Nature Conservancy at 757-442-3049, the
Virginia Department of Conservation and Recreation's Natural
Heritage Program at 757-787-5576, Chincoteague National Wildlife
Refuge at 757-336-6122, Eastern Shore of Virginia National
Wildlife Refuge at 757-331-2760, or the Virginia Department of
Game and Inland Fisheries at 757-442-2429.
Table 1. 2003 piping plover
productivity estimates for all sites monitored for reproductive
success in Virginia. Productivity is calculated by dividing the
number of chicks fledged by the number of pairs monitored.
|
Site |
Pairs monitored |
Chicks fledged |
Productivity estimates
(2001 estimates) |
|
Assateague Island* |
39 |
76 |
1.95
(1.56) |
|
Assawoman Island* |
15 |
32 |
2.14
(1.13) |
|
Metompkin Island |
31 |
52 |
1.68
(1.07) |
|
Cedar Island |
16 |
32 |
2.00
(1.00) |
|
Statewide estimate |
101 |
192 |
1.90
(1.19) |
|
*
Data provided by Chincoteague National Wildlife
Refuge. |
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Figure 1. Annual number of piping plover breeding pairs in
Virginia, 1986 – 2003

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Figure 2. Annual statewide piping plover
productivity estimates in Virginia, 1990 – 2003. Blue line
represents the fledge rate (1.24 chicks per pair) necessary to
maintain a stable population.

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