Terns are Elegant

Please consider the images to be copyrighted and ask permission before using. Thank you; DEClapp

People along the coast see terns quite often – if they look. Yet many people never see what is surrounding them. At the beach there may be fish, whales, seals, gulls, terns, sandpipers and mollusks as well as sand, water, blankets, and people. Look around!! Gulls are pretty common on most salt water beaches and many fresh water beaches as well. They get a bad rap as “flying rats” and scavengers that might steal a sandwich from you or your child. In most places our rubbish is now collected and buried (big picture comment) and the loss of this easy food supply has been part of the reason for a decline in gulls over the past decade or two – and they seem to be less of a beach nuisance unless people are feeding them. The gulls are the most usual of beach wildlife sightings. But, terns are there – just off shore cruising over the water..

In many cases where there are gulls there are terns. This is a group of slight, delicate, pale birds that fly with ease. They migrate long distances and live twenty or more years. In the western north Atlantic (Gulf of Maine) we have the Common Tern (COTE), Roseate Tern (ROTE) and the Least Tern (LETE) as summertime breeding birds. The Common Terns nest in large colonies usually on predator-free islands. The Least Terns nest in loose, smallish, colonies wherever they want – often on beaches where people and off-road vehicles might find them. Roseate Terns nest only on a couple small islands deep in Nantucket Sound, but after fledging the young they will stage out on the Atlantic beaches before migrating south. August and September can be a time were 20-40,000 terns can be in the Monomoy/Chatham area. Though this sounds great for birders, the ability to get out to the sand bars and islands where the birds are is now very limited due to the erosion of the sandy cliffs and the creation of great shoals that make boat travel near impossible throughout this area. For instance what was once called South Beach, and allowed for access to miles of sand spit, now has been broken and flattened by the sea, no longer providing access or the right conditions for birds. Things change very rapidly along this sandy coast.

In the spring, during migration, we see a few Arctic Terns (ARTE), Black Terns (BLTE), and Caspian Terns (CATE). Scattered throughout the warmer weather we will have very occasional reports of Sandwich Tern (SATE), Royal Tern (ROTE), and Forster’s Tern (FOTE). A Massachusetts birdwatcher with modest dedication will see five or six species of tern; listers and chasers might see seven or eight species.

The following images are of several species but feature the Common Tern colony on Monomoy Island. It is closed to visitation this year through the impact of the COVID-19 troubles – usually there is a US Fish and Wildlife team out there monitoring the colony from a permanent tent-based camp. But not this year. There are about 11,000 pairs of Common Terns out there with some Laughing Gulls and maybe a few Roseate Tern pairs as well. The most common nesting sandpiper type is a large and rather plain (until it flies) bird called Willet (WILL).

The Black Tern nests in marshes and swamps. It is a light flier and very buoyant as it goes about its work. Even though they nest over fresh water they are regularly seen migrating over salt water, very often well off shore.
The Least Tern is about the size of a Northern Cardinal; smaller than an American Robin. In addition to the Atlantic coast population they are found inland along the main rivers of the US and there is a population on the west coast as well. The inland and western populations have been listed as “threatened” and the eastern population as a “species of concern”. This circumstance occurs because they invariably choose beaches where humans recreate. The birds often come out on the short end of the stick when off-road vehicles, beach-goers, and dogs are involved. They are a delicate bird but with a direct and strong flight.
The yellow bill with a black tip is diagnostic when seen on a small tern.
They have rather long wings for a small bird and are strong fliers. They feed by plunge diving for fish, small fish as you might imagine, in shallow water usually over sand flats.
They are quite common throughout New England beaches now as the Park Service, Fish & Wildlife, and many towns and private agencies have protected their nesting sites along with the protection given to the diminutive Piping Plover (PIPL).
The most common tern is the Common Tern. Like all the terns this is a migrant with many miles under its feathered belt. The orange bill with a black tip is characteristic and often easy to see. They nest in large colonies and are most successful when nesting on islands where predators are limited. In many colonies Great-horned Owls (GHOW) and Black-crowned Night-Herons (BCNH) are the greatest threat as they can fly in from offshore. When they nest in main land colonies they will abandon if something like a Red Fox begins to take eggs or chicks (or perhaps a weasel or mink or coyote or gray fox or raccoon or skunk, etc…).
They are very similar to the Arctic, Roseate, and Forster’s terns in appearance. It seems the gray mantle with light colored wings with darker tips to the flight feathers is a very workable design for doing what terns do. They nest inland as well as coastal. The young leave the shallow scrape of a nest after a couple days but hang around near the nest site for 3-4 weeks. After fledging the young will follow the adults for another 6-8 weeks.
The colonial birds will rise up in a “fright flight” at the mere presence of something odd. In some cases it seems that if one bird sees a shadow they all will bolt into the sky. When something, or someone, actually enters the colony they will fly at the intruder, calling loudly, and try to drive it away by constantly bothering it. It is usually a noisy and often smelly trip through a tern colony.
The largest colonies are all well managed and protected. The US Fish and Wildlife Service manages the colony nearest to me. They census and monitor the colony throughout the nesting season. As the Roseate Tern is a listed bird there can be some management of predators in order to allow the Roseates the best chance of nesting success.
Counting nests and eggs is a tedious job; walking shoulder to shoulder through the colony locating, avoiding, counting, and recording the many thousands of nests.
The Roseate Tern is similar to Common and Arctic. It has a longish black bill and flight feathers that are quite pale. It may be hard to perceive from the pictures but it is lighter overall when standing with a bunch of Common Terns. The youngster has a scalloped pattern to the back feathers, a characteristic of the young roseate.
The general pattern of “tern-ness” carries over to this larger tern; the Royal Tern. This its mostly a southern coast and Gulf of Mexico resident but we see them every year up in New England. They are generally gray and white like so many other terns. By the way a few of the pure oceanic (pelagic) terns are not gray and white. The two types of noddies, the bridled, and the Sooty terns are strikingly different looking; noddies are brown all over and the bridled and sooties are black and white with lots of black.
There are a couple terns that have a distinct winter plumage. They all change “headgear” for the winter but the Forster’s Tern develops a mask and loses the black cap. In breeding plumage it has an orange bill with a black tip and a full black cap. It is a bird that nests on inland wetlands west of the Mississippi River and up into southern Canada. We see it here in the east after breeding. They are one of the few terns that can be found along our coast (usually well south of New England) in the winter.

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