Abird's-eye view of Bull's Island . By Chris Dixon
Edition: FINAL,Section: NATION, Page A1
ChrisCrolley has seen scores of birds in his life, but this season theBull's Island ferry operator and Cape Romain naturalist has beenimpressed by the ducks and other winged creatures wintering on theCharleston County island.
Cruising outaboard the ferry on a breezy late December morning, he gave amplereason for bird lovers to visit this pristine wilderness at thesouthern end of the Cape Romain National Wildlife Refuge. "Thepopulation of migratory waterfowl this year is impressive," he said."I've never seen so many canvasbacks in one place before in SouthCarolina."
Early this month,the U.S. Fish and Wildlife Service will conduct its annual midwintersurvey of waterfowl by holding counts in national wildlife refuges upand down the Eastern seaboard. Using aerial and ground-based counts,biologists take a day's snapshot of prime waterfowl habitat along theso-called Atlantic Flyway — a migratory bird route stretchingfrom Maine to Florida. The survey does not determine the harvestallowances for duck hunters, but according to South CarolinaDepartment of Natural Resources biologist Dean Harrigal, it isimportant in determining long-term trends and shifts in waterfowlpopulations.
"It's a snapshotout of a plane window at a given moment," he said. "It is not anabsolute count by any stretch of the imagination."
Harrigal saidwaterfowl counts in the state had been trending downward during thepast decade, particularly in the Santee Cooper lakes region, wherehabitat changes have led birds to bypass the areaalmost entirely.This makes Bull's Island, the Santee River Delta and the ACE Basinmore important wintering spots.
"Bull Island hastraditionally held a good number of waterfowl," he said. "And onething you see with the season in, is that birds tend to gravitate towhere they're not being bothered. That's the important role that ourinviolate refuges play in providing a place for birds to rest and nothave disturbances."
The notoriouslydifficult job of counting the transient bird population around Bull'sIsland has fallen for more than a decade upon the shoulders of Fishand Wildlife biologist Sarah Dawsey. From the time migratory birdsarrive in November until they migrate northward in March, Dawseyconducts weekly counts.
On Dec. 22,Dawsey counted 8,107 migratory waterfowl on Bull's Island, a healthynumber that was up 1,500 from her previous week's count. Numbersoccasionally exceed 10,000 on particularly good weeks. Of the 5,222ducks on her recent survey, Dawsey counted 81 blue-winged teal, 382green-winged teal and 788 canvasback. Among the nonduck species, shecounted nearly 2,500 coot and 162 pied-bill grebe.
"Numbers arelooking good this year," she said. "We're seeing lots of divingducks: canvasbacks, scalps, ringnecks, wigeons, gadwalls andgreen-winged teal. A lot of them breed in Canada and the coldermiddle U.S. and basically work their way down the Eastern seaboard asthe temperatures drop."
Motoring out tothe five-mile-long Bull's Island, Crolley pointed out not onlyairbound ducks, but also sharp-shinned hawks. In front of the pontoonboat, a pair of American loon dove for fish while an orange-beakedflock of American oystercatchers hunted off the starboard rail."Those beaks are evolved and adapted to feed on oysters," he said."There are huge beds of oysters out here, and when those oysterscrack open a fraction of an inch to filter feed, those oystercatchersslide their beaks into the shell, clip the abductor muscle and removethe oyster. We have the concentrated majority of the Americanoystercatcher population in Cape Romain. They're a beautiful bird andpeople come from all over the world to see them."
Bull's Island isespecially important to at least 277 species of migratory andpermanent birds because of its unique combination of freshwaterlakes, reed-filled marshes and dense maritime forests of oak, cedar,loblolly pine and sabal palmetto. The wetlands running along theisland's 16 miles of trails are fished by great egret, blue heron andbald eagle, while rare peregrine falcon cruise for feathered prey.
Stopping alongone pond, Crolley pointed to a single hooded merganser preening itsfeathers just as, overhead, an osprey dove for fish. "The osprey doreally well out here," Crolley said. "American bald eagles willactually sit and watch them hunt and when they catch a fish, theeagles will go out and steal their prey."
Crolley walkedthrough forests thick with Bull's Island's bewildering variety oftrees while birds of all feathers flew overhead. The wax myrtle tree,he said, is so named because female trees produce a fruit that can beused for candles. The yaupon tree, better known as the holly, iseasily identified by its red berries, and the invasive popcorn treeproduces white berries from which the tallow can be used for soap.
At Bull'sIsland's north end lies Boneyard Beach. Ceaseless erosion here hasled miles of dense forest of cedar and oak to become beachfrontproperty. Here, a rare white pelican flew above the equally bleachedbranches and trunks of the long-dead trees.
Just inland fromthe Boneyard lay Alligator Alley, Moccasin Pond, Jack's Creek and anassortment of huge reptiles and wintering birds. An alligator atleast 22 feet long sunned itself on one bank. "Alligators aren'tsupposed to get that big," Crolley said.
Along the broadwaters of Jack's Creek, a carpet of ducks swam, dove and bickered."That's absolutely ideal migratory waterfowl habitat," Crolley said."The food source is plentiful with the wigeongrass and other aquaticplants, and the little fishes for the divers and hooded mergansers.
"It's just agreat phenomenon of migration where these ducks just fly thousands ofmiles from one place to another," he said. "Some fly from upperCanada all the way to South America. They move farther in their livesthan any other creatures on the planet."
It was on thehundreds of watery acres around Jack's Creek that Crolley said hetypically sees the greatest concentration of ducks. The northern edgeof the creek also lies close to Bull's Bay and the pelagic, or openocean, birds that feed not among the reeds but among the rollingswells. "It's a very dynamic edge between ecosystems," he said.
And although thecurrent run of ducks is remarkable, DNR biologist Harrigal said astrong cold or warm front could send the ducks scampering south ornorth at a moment's notice.
"A lot of what wesee is weather-dependent," he said, "and a lot is duck-dependent.Ducks are just like people — they do what they wanna do."
Contact Chris Dixonat firstname.lastname@example.org or 745-5855.