When Camouflage Kills

Camouflage, defined by Wikipedia as “the use of any combination of materials, coloration or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else,” is a very effective survival tool. Many animals blend into their surroundings so seamlessly that predators don’t detect them. Shorebirds are among the species that have used this strategy successfully; but now, with their nesting habitats riddled with human activity—sometimes perfectly well intentioned activity—blending into their surroundings can mean possible death.

Shorebirds live, feed, and nest on beaches and can be seen along Louisiana’s shoreline and barrier islands at different times of the year. These birds, including plovers, terns, knots, and sandpipers, are some of the fastest disappearing species. Apart from increased human activity on beaches, coastal land loss, development, and degradation to coastal marshes have had a negative impact on these species.

Except in breeding plumage, shorebirds are drably colored birds, outfitted in fifty shades of brown and white, which makes species identification a challenge for bird watchers and shorebird counters. But that cryptic coloring is pivotal for the survival of eggs and chicks on the beach during nesting season. Blending in like bits of white shells in the brownish sand, camouflaged eggs and chicks are hidden from circling gulls, coyotes, and other predators in search of their next meal. The nests of Wilson’s Plovers and Least Terns don’t resemble classically shaped bird nests either. Instead the birds make a scrape or shallow indentation in the sand to lay their eggs.

Camouflage would normally allow the majority of these chicks, excepting normal levels of predation found in nature, to reach adulthood. This changed when our southern beaches became a popular mecca for fisherman, sunbathers, joggers, campers, and four wheelers, all producing traffic that’s at its heaviest during nesting season. Since the chicks and eggs are so cleverly camouflaged in the sand, they can get trampled and run over before they are even noticed. Their invisibility is a death trap.

Audubon Louisiana, the state office of the National Audubon Society, started a program three years ago in coastal Louisiana to aid the shorebird population during the breeding season, when beach-goers are at peak numbers. The goal is for both humans and birds to co-exist peacefully on the shoreline. Biologists with Audubon’s Coastal Bird Stewardship Program find and mark Wilson’s Plover and Least Tern nests during the nesting season, from April to August. The nests are marked with “symbolic fencing,” posts with signage, that alerts beach participants to nest sites.

Working throughout Grand Isle and Cameron Parish, the Audubon biologists count and monitor nests and chicks. They also recruit local volunteers to help safeguard the nests from unsuspecting people and dogs and to talk with residents and visitors about the program. Residents learn that activity right next to nests can scare birds away from incubating their eggs and/or chicks. Left exposed for just ten minutes in the summer’s intense heat, eggs will cook and chicks will die.

Another threat that beach-nesting birds face is the loss of their habitat as beaches erode and sea levels rise. An important restoration strategy involves planting native species of grasses and other dune vegetation, which also provide important habitat to birds and wildlife on the coast. These plants play an important role in trapping sand to stabilize and create dunes. Many conservation groups and volunteers hold planting events to help improve these coastal habitats, a valuable practice that, ironically, can have short-term negative impacts if held during the nesting season. Little chicks hiding in the vegetation are easily stepped on, and the disturbance can cause parents to abandon their eggs and chicks.

This next spring and summer, when you are visiting a Louisiana beach, be alert to signs that our feathered friends are hanging out there too. Audubon’s poles, or “symbolic fencing,” offer one telltale sign that there is a nest close by. Shorebirds also display behaviors that can alert you to the fact that you are encroaching: Aerial chasing, sharing food, and digging shallow depressions in the sand are signs of courtship, while feigning broken wings, diving at intruders, and flying in low circles without landing signal distress.

If you have to drive on the beach, stay below the tide line to avoid running over nests or chicks. Another good idea is to not disturb washed up vegetative debris, or wrack, since it provides important food and roosting habitat for birds.

With these precautions in mind, you’ll be surprised how entertaining it can be to watch the birds at the beach. Try it next time!

For questions or information, email Harriett at hpooler@audubon.org.

To learn more about Audubon’s program and how you might volunteer, visit la.audubon.org/coastal-stewardship-program-1.