Saving Our Shorebirds

GPS tracking at the beach is now a reality for hundreds of threatened shorebirds. Regular beach-goers can identify numerous shorebirds that make an appearance along the East Coast, gobbling up tiny crabs, mussels, clams, and fish. Some of the bird species have staggering migration patterns, traveling thousands of miles over the course of the season. And some are finding that trip more and more difficult due to habitat loss and diminishing food supply.

One of those species is the red knot, a small bird about the size of the robin that relies on horseshoe crab eggs, mussels, and clams for the majority of its diet. The birds travel in huge flocks, making stops along the East Coast during their migration from South America to the Arctic. In order to track the migration of the red knots, scientists have begun using GPS tracking locators as part of their research process.

GPS Tracking and the Red Knot

Wildlife researchers have expressed concern that the red knot population has decreased by 75 percent over the past thirty years. As part of an effort to learn more about the habits and needs of the species, a group of researchers captured and tagged a flock of red knots that were making a stopover on the Cape Cod shoreline. Each bird was fitted with a GPS locator, measured, and weighed before being released. Scientists hope the devices will provide information about where the birds routinely make stops along their migration route.

The program is designed in part to determine whether the red knots should be added to the federal list of endangered and protected species. It has already been designated as an endangered species in the state of New Jersey.

How GPS Supports Animal Studies

GPS tracking for the purpose of studying animals has been used in a wide variety of circumstances to study animals on almost every continent. The technology has given scientists insight into animal behavior patterns that could never have been obtained otherwise. Because GPS can go where human beings can’t, it can record information like migratory patterns, animal movement within a region, and locations of individual animals over time. All of the following animals have been studied and tracked using GPS technology:

Animal Studied	Behaviors observed
Whales	Feeding patterns, behavior under ice layers, diving depths, response to various conditions in the water
Lions	Social structure, feeding patterns, population, roaming habits
Deer	Home ranges and movements within the range
Wolves	Roaming patterns, attack prevention, protection of ranch herds
Elephants	Habitats, herd movements, protection from poachers
Sharks	Feeding habits, breeding locations, attack prevention

 

These examples represent just a small handful of the animals being tracked by scientists using GPS technology. Not only can scientists observe behaviors directly, but many of the devices can also send text messages or tweets at intervals, making it possible to create a timeline of the animal’s behaviors and habits.

What’s Next for the Red Knot

Federal administrators hope that the red knot will be added to the threatened species list in order to receive protection under the Endangered Species Act. GPS tracking will be a key part of the decision. By providing accurate information about the bird’s habits, migration behaviors, and feeding locations, scientists will be able to determine whether its primary stopover points are significantly affected by climate change, habitat loss, and diminished food supply.

Red knot stopover points have been observed up and down the east coast, including:

• Canadian Arctic


• Delaware Bay


• Southern Chile


• Argentina


• Tierra del Fuego

Knowing these locations can help scientists determine which food sources the red knot relies on, enabling them to identify the relationship between food sources and population growth or decline. Based on this data, biologists have discovered that the red knot feeds heavily on horseshoe crab eggs such as those found in Delaware Bay. As the horseshoe crab population declines, scientists have observed a corresponding decline in the size of red knot flocks that stop in those locations. Biologists hope that adding the red knot to the endangered species list will make it possible to protect their habitats from human interventions that contribute to species decline.

Although the red knot is one of the most well-known shorebirds, it is by no means the only one in danger of drastically reduced populations. Scientists estimate that nearly 70 percent of shorebirds are shrinking in numbers. They blame the decline of these species on loss of food sources at key stopover points, habitat changes due to human intervention, and climate change. By providing the data needed to pinpoint specific locations relied upon by migrating shorebirds, GPS tracking plays an essential role in the preservation and protection of these animals. Conservation workers plan to recapture the birds at a later date, observe the changes in population and animal condition, and continue the study with the goal of protecting the lives and homes of these beautiful and plucky little birds during their 10,000 mile migration journey.

Saving Our Shorebirds