Grazing, dogs, and climate change could be contributing to a decline in bird populations in the area.
In the austral springs of 2021 and 2022, freelance environmental consultant Ryan Irvine surveyed the breeding-bird populations across Cape Pembroke.
Responding to anecdotal evidence of decreasing birdlife in the area, Ryan applied for funding from the Environmental Studies Budget.
The budget is administered by the Falkland Islands Government (FIG) and funds are allocated on a yearly basis.
“I was surprised there’d never been any breeding-birds survey done,” he told Falklands Radio this week, “especially inland, where there are quite a lot of breeding birds. There was no hard data to support the idea that populations had been declining. So I decided to do these surveys, basically as a baseline.”
Covering the whole area (the peninsula North of the Boxer Bridge-Surf Bay line) in about 15 mornings, Ryan also wanted to find out what might be causing the alleged declines.
“Climate change is probably the most obvious thing,” he said.
“The ponds and boggy areas are drying up – and even by the end of winter some of them haven’t filled up. Species which require a certain amount of wetness – things like snipe, double-banded plovers, or rufous-chested dotterel – are the ones most likely to be effected.”
Other suspected causes are more directly man-made.
“Grazing is an issue as well, especially in combination with the drying of the area. In the past, the area used to be limited to 25 horses in the winter; but in the two winters prior to me doing the surveys I counted over 80 horses, and over 60.
“So you’ve got more grazing, and less growth, and large areas are becoming more like peat-dust: more and more of the Cape is becoming less suitable for breeding birds. And once the birds go, or the habitat is destroyed to a certain extent, it will be very hard to resurrect.”
Dogs, especially off their leads (the overwhelming majority, in Ryan’s estimation), are also a problem, and he feels the rules probably need to be toughened up.
“Even though Environmental Department advice is there, it’s being ignored. I found several nests on or near to popular walks, that had been abandoned. [The birds] only abandon them due to disturbance.”
Asked if the dual roles of Cape Pembroke as common land and also a nature reserve is incompatible, he said: “I think there is a bit of a conflict there.”
He suggests some concerted replanting could restore most of this habitat, but also argues more control over the use of the land is necessary.
“If you want to protect the breeding birds, then – if walking dogs on a lead isn’t going to be enforced – there probably needs to be a total ban during the [September-January] breeding season.”
Ryan wants the survey to be a long-term prospect, so he also trained local scientists to continue with it.
“Either yearly or every two years, depending how much time they have. Hopefully this will soon become a long-term data set, and we can start mapping the declines – or, if we’re lucky, increases – in populations.”
Ryan is currently finalising his report, which he says is is due on FIG’s desk sometime around July or August.
Meanwhile, he says, it might be beneficial for surveys to cover other parts of Stanley Common, such as Phillips Point.