Impressive Seabird Tough Guys      

Gulls: Flyboys of the Sea   

 Fourth in the seabird series

                      by Tara Spears

These sleek, soaring seabirds have long been the inspiration for artists and fishermen, such as the popular 1970’s Jonathan Livingston Seagull book that epitomized the self-discovery movement and spawned movies, posters, and music. What is it about these medium sized birds that captures the human imagination? Perhaps it is their effortless flight and diving antics as they pilfer food from pelicans or your picnic lunch that is so entertaining:  a day at the beach watching the gliding gulls is guaranteed to make you smile.

A Pacific species, the Heermann’s Gull, (above picture) can be seen on the Riviera Nayarit coastal areas during the winter and spring months until late May when they begin their migration north along the US and Canadian Pacific coast.  Unlike many other seabird species, Heermanns do not fly in large flocks; in fact, large groups of this gull are only seen at roosting sites such as small, offshore islands, kelp beds, sandy beaches and estuaries.  We are very fortunate to have the largest breeding colonies off the west Mexican coast: 95% of the world’s gulls breed here! The gull’s main diet is fish and other small marine creatures, but they are also known to eat eggs, trash, and carrion. Both parents incubate the 2-3 eggs for about four weeks. Both parents then bring food to the nestlings until they are old enough to fly and feed themselves.

In Mexico, there are several Important Bird Areas that protect Heermann's Gull breeding grounds, including Isla Benitos, Isla Angel de la Guarda, and Isla Rasa, which supports 300,000 breeding birds.

NOTE: The inland gulls that you see in the northern interior of the USA and Canada are a different species than those viewed here along the coast.  The interior species are more scavengers whose diet consists of carrion and garbage- hence the large flocks around trash dumps.

 Compare the picture of the adult Herring gull, left, with the adult Heermann gull, right. Note the different colored legs and beaks besides the plumage. The Herring gulls are the most familiar and widespread of the gull species and are what most people think of as seagulls. This big bold bird is around 25 inches long and has a wingspan of almost 60 inches. As a young bird it is brown with scale-like patterns, but as an adult it is white with grey wings, a red spot on the lower beak, and black back feathers.

Herring gulls are sociable birds who hunt, migrate and feed together. Herring gulls are long lived as far as birds go. In captivity, the longevity record is 44 years and in the wild 36 years. Males and females are virtually indistinguishable, however the male is slightly larger. This seagull is best known as a scavenger. It is most often seen in large, noisy flocks congregating where food is available, around fishing boats, picnic grounds, parking lots and garbage dumps. Many people consider it a nuisance, but the gull performs a valuable service. It scavenges up great numbers of dead or injured animals and organic litter which could pose a health threat to humans. The call of the gull is a distinctive, shrill, screechy “Eurl” repeated incessantly.  Gulls flight behavior is characterized by strong, direct movements with deep, steady wing beats and gliding on thermals and updrafts.

Seashore gulls will pick up clams, minnows, barnacles, mussels and crabs from beaches. Gulls are not good fishermen, but they are good scavengers.  They are important in cleaning up harbors and beaches. It is so enjoyable to watch the patient, persistent seagulls pick up shellfish and drop them from the air onto a rock, road, or car to crack them open. If the shells do not break they will repeat the process indefinitely.  Seagulls are known to follow large ships across the ocean, feeding on the garbage that is thrown overboard.

Feeding gulls should be strongly discouraged as they learn quickly.  If hand fed, the braver birds will take food directly from you, and confidently begin to snatch human food, whether it is offered or not. If Herring Gulls are not provided unnatural meals, they will turn to a more natural source of food. Another interesting characteristic of gulls is that it drinks salt water because it has a special gland that filter out the salt.

 These amazing flyers will sometimes hover over foraging blue fine tuna that are eating fish and squid because the large schools of fish force the bait close to the surface where the gulls can easily grab a meal.  Recently European scientists have learned that gulls of different ages spend time in different locations- that they are segregated by age, much like teens and adults at a mall.

Whether you appreciate the seagull for its marvelous flight, delightful feeding antics, or its valuable role in the ecosystem, these familiar flyboys are an asset to the Riviera Nayarit. 

Heermann gull   

                                                     roosting island Guayabitos

Kittiwake gulls                                                              gull breeding/migration area

Contact Tara:   tara.sprs@hotmail.com