Barry John McMahon, University College Dublin
There are few sights more joyful than a dog bounding through the countryside. But for ground-nesting birds and other wildlife, the experience is quite different.
Letting a dog off its lead can disturb several species without the owner even noticing. And with spring and summer approaching, the breeding season for a vast array of wildlife, some environmental charities are urging people to keep their dogs under control and to stick to paths when walking in nature reserves.
The law already obliges dog owners in the UK to keep their pets on a lead no longer than two metres between March 1 and July 31 when on land with public right of access.
To be clear, the destruction of habitats as a result of changes in how the land is used, including intensive farming and road building, is a far greater cause of wildlife decline than anything the average dog is capable of.
But birds which build their nests and incubate eggs on the ground, such as curlews, yellowhammers and skylark, are put at greater risk of losing their offspring as a result of being disturbed.
A dog bursting through the undergrowth of a woodland or lolloping through tall grass on a moorland can flush out and frighten adult birds incubating their eggs in well-hidden nests.
The unguarded eggs and chicks are an easy target for predators, but even if they escape becoming a fox’s next meal, they may be abandoned. While certainly not the biggest threat to wildlife, your overly enthusiastic dog is another risk to the viability of eggs and chicks during a critical time of year.
Unintended consequences
The vulnerability of ground-nesting birds is reflected in statistics. Around 66% of ground-nesting species are in decline in the UK, compared to 31% of species which don’t nest on the ground, such as robins and blackbirds.
The energy that nesting birds use up to flee their nest can be considerable, especially if they are already under stress from having laid eggs. This may make them more vulnerable to disease or being eaten themselves. Research shows that birds are less likely to nest near trails in grasslands as a result.
The modern landscape, with its matrix of intensive farms, conifer plantations and roads, favours generalist predators such as foxes and crows which can swoop in and gobble up abandoned eggs and chicks. Although the exact causes of any species’ decline can be difficult to pinpoint, one study demonstrated that a leading cause of the low survival rate of curlew chicks was fox predation.
A crow, noticing a disturbance created by a person and their dog, can locate a nest when they otherwise wouldn’t have spotted it. Crows also appear to be more tolerant of these kinds of disturbances and will return to a site quicker than other species.
Although the impact on ground-nesting birds is unintended, disturbance by dogs during the breeding season is one threat to wildlife that people can easily prevent. Try letting your dog run free on fields or parks away from wild margins where birds may be nesting.
Ground-nesting birds are in a perilous state in the UK and across Europe. All possible efforts should be made to prevent them declining further, including keeping dogs on leads in spring and summer. Giving these species the best possible chance to maximise the number of healthy chick they produce is one way you can help.
More tips for wildlife-friendly pet ownership
- Don’t let your dog jump in ponds. Not only can this disturb the fish and amphibians living there but chemicals in your dog’s flea treatment can poison the water.
- Always pick up after your dog. High levels of phosphorous and nitrogen in dog poo can over-fertilise the ground and disrupt the ecology of a habitat, as well as spread disease.
- Cats kill a lot of wildlife. Try to keep them indoors, but failing that, add a bell to their collar to warn potential prey.
Don’t have time to read about climate change as much as you’d like?
Get a weekly roundup in your inbox instead. Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. Join the 10,000+ readers who’ve subscribed so far.
Barry John McMahon, Associate professor of Wildlife Conservation & Zoonotic Epidemiology, University College Dublin
This article is republished from The Conversation under a Creative Commons license. Read the original article.