One birder called to the others, pointing to a distant dead tree adjacent to Anegada’s runway.
To the naked eye, the bird perched there was barely more than a small white dot. But when it spread its wings in flight, it was easily recognisable as an osprey.
This was the final day of the National Audubon Society’s annual Christmas Bird Count on Friday.
The worldwide event began in 1900 when ornithologist Thomas M. Chapman proposed a “census” where birds would be counted instead of hunted. More than a century later, people around the globe flock to lookouts and other avian hot spots to tally what they see.
The Virgin Islands has participated in the annual count since 1988 on Tortola and Anegada, submitting to Audubon the number of participants, hours spent counting, species seen, and birds counted.
“Anegada is situated in a really unique situation,” explained Nancy Woodfield-Pascoe, the deputy director for science, research and environmental policy at the National Parks Trust of the VI. “It’s right at the tip of the archipelago of the whole Caribbean.”
This location, Ms. Woodfield-Pascoe said, is squarely in the middle of many birds’ migratory routes.
Anegada trip
On Friday, Ms. Woodfield-Pascoe boarded the ferry on Tortola with United Kingdom botanist Dr. Colin Clubbe and VI ecologist Clive Petrovic to conduct Anegada’s bird count on the final day of the event.
“There’s a period that the National Audubon do it, from like mid-December to basically today is the last day: January 5,” Ms. Woodfield-Pascoe said. “They try to count all the birds in North America and the Caribbean, just to see where the birds are. It gives a snapshot of what’s happening bird-life-wise at that time.”
To keep an eye on the birds of Anegada during the rest of the year, Ms. Woodfield-Pascoe relies on NPTVI Warden Rondel Smith Jr., a young Anegadian.
“He’s an excellent birder, and he captures wonderful photography,” Ms. Woodfield-Pascoe said. “He kind of keeps an eye out all year round on the bird life.”
Before meeting with Mr. Smith, the trio of birders, each scientists in their own right, stopped at a couple of favourite locations before reuniting at Fishermans Wharf.
How?
As small as the islands of Tortola and Anegada are — compared to the United States, for instance — attempting to count all the birds on an island in one day is impossible.
“Audubon lets you count the week preceding the day of the count. So if you don’t see a certain bird on count day but you saw it the week before, you can include it as a count week bird,” Ms. Woodfield-Pascoe said. “Because sometimes the weather doesn’t cooperate or you just don’t see [anything].”
Mr. Smith had performed a count on Anegada’s east end earlier in the week, Ms. Woodfield-Pascoe explained.
“We only have one day to do it and we’re trying to get as many all over,” the deputy director said.
Same spots
After securing a rental car, Ms. Woodfield-Pascoe, Dr. Clubbe and Mr. Petrovic took a moment to count all the birds they could see at the Anegada Reef Hotel.
“We always come here for ruddy turnstones; you always see[them] walking on the sand,” Ms. Woodfield-Pascoe said. “We kind of have this set routine because they’re just so reliable. When you walk up to the edge of the chairs and look down, they’re usually walking up and down.”
Following the same route every year gives the count more consistency, establishing a reliable baseline to which previous years can be compared, according to Ms. Woodfield-Pascoe.
“We’ve come to know what to expect here,” she said. “So when you’re seeing something new … certain things can get picked up through bird counts that you might not [normally see]. You know, you’re going about your business every day, but you’re not really paying attention.”
Invasion
While explaining how discoveries are made during bird counts, Ms. Woodfield-Pascoe noted that some of the discoveries are signs of globalisation.
“You can hear all the little cheeping? Those are English house sparrows. So, like, how are English house sparrows here, right?” she said. “They come through shipping containers. Birds will come in and get trapped in shipping containers, and now we have them down on Tortola. You won’t see them out in the wild; you’ll see them around buildings and built-up areas.”
Sparrows are just one of many non-native species in the VI.
“There’s a lot of green parrots on Tortola now we didn’t used to have,” Ms. Woodfield-Pascoe said. “Those are escaped pets. [Green parrots] kind of look as if they’re getting established. At first there was just a few, but now there are so many. Some birds can become invasive; some just become naturalised, and they’re not really a problem.”
Non-native species can indicate gaps in the territory’s biosecurity, according to Ms. Woodfield-Pascoe.
“Unfortunately, because a lot of our shipping is coming from Florida, what might be an invasive there could be a problem for us if we don’t have good biosecurity,” she said. “That’s something that government is trying to address, this biosecurity legislation.”
But the problem is challenging considering the number of shipping containers that cross VI borders and the task of searching each one.
Invasive pine
One of the most visible invasive species on Anegada is the Australian whistling pine. Across the west end of the island, the wispy green trees cover much of the sandy area.
“The Anegada Reef Hotel planted three [Australian whistling pines] here in the mid-sixties as a shade tree,” said Dr. Clubbe, a senior research leader at the Royal Botanic Gardens, Kew, who is in territory for three months conducting a regular botanical review of the VI’s flora.
According to Dr. Clubbe, the Australian whistling pine produces “lots of viable, easily trans-mitted seeds,” which took over Anegada’s west end by out-competing native species.
“[Australian whistling pines] do two things. One, because it has very acidic needles, it prevents the establishment or reestablishment of the native plant community,” Dr. Clubbe said. “The other thing [a master’s student] also found: Because it’s so shallowly rooted, it stabilises the sand; turtles that nest up at the beachline above the high tide mark … can’t now find good areas to dig out to lay nests.”