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Randall Morgan on The Amazing Tern

First, we'd like you to meet Randall Morgan, Hilltromper's unofficial Naturalist-in-Residence.

Aug. 14, 2014—Among Santa Cruz's rich community of amateur and professional naturalists, conservationists and nature geeks of every variety, Randall Morgan is respected and beloved for his knowledge, passion and wit.

He has spent more than 40 years documenting the bird, insect and plant life of Santa Cruz County, in the process discovering many species of plants and several insects.

A fourth-generation Santa Cruz County native and UCSC alumnus, he has for many years worked to protect rare species and ecosystems locally, resulting in the creation of several natural reserves and parks—including the Randall Morgan Sandhills Preserve. He is a fellow of the California Native Plant Society and a specialist in Trifolium (clovers), Piperia (rein-orchids) and other genera.

We quizzed Randall about the terns we've been seeing dive-bombing our near-shore waters for the past several weeks.

Here at Hilltromper HQ we are damn curious about the wonders of the wild around us and we know you are too. We want to spread some knowledge, and Randall has agreed to help. If you have a question about local birds, plants or bugs, put it in the comments section below, or email it to traci@hilltromper.com and we’ll ask it!


Hilltromper: So we're seeing terns all over town, and we’re wondering what kind they might be.

Randall Morgan: We have three species that are pretty common. They come in small, medium and large sizes. The small one is Forster’s tern, it has a forked tail and a black bandit mask and is usually seen on the wing, solitary or in small groups. They're around nearly all year in small numbers.

The medium-sized tern is the Elegant. They breed at Isla Raza island off the Baja California coast and come up here kind of irregularly, sometimes in large numbers during summer after they’ve bred down south. It depends on the currents—what fish are here and that sort of stuff. Some years are really good for elegant terns and some are not. This is an especially good year for elegants. They’re probably the most common tern you’ll see on beaches.

The third is a large one, the Caspian tern, it’s a worldwide tern, named after the Caspian Sea, of course. It’s got a real thick, cigar-looking red bill and a raucous voice. Those arrive about April. You can hear them flying overhead. It’s kind of a rrRAUGH! They commute between the South Bay and the ocean here, and you can often hear them high overhead, flying in pairs or small groups.

Later, when the babies are grown and on the wing, you can hear the adult making this scrawking sound and the baby answers with a little squealing sound. The Caspian tern is almost the size of a gull.They breed in the South Bay. They like to go to open salt flats, where they’re safer from predators.

How does a person know if they’re looking at a tern, as opposed to a seagull?

Terns are more slenderly built, they have more elegant proportions than a gull. They have a way of feeding that’s distinct. They dive into the water, like a pelican, whereas gulls scavenge around here and there. They also have a red or orange bill, whereas gulls have a yellowish bill, often with a red or black and red spot. Also the bill is very slender, pointy. And the legs are short and red or black, versus yellow or pink in gulls.

And they have a kind of crest also, which is black in the breeding season. So that’s one thing. And also, terns have a forked tail like a swallow, whereas gulls have a square tail.

How long willl Caspians be here?

They stay through the summer, pretty much. They winter along the coast of Mexico, mainly. Though since they’re worldwide, they have a lot of different destinations.

Are they following any particular kind of fish?

Well, any fish small enough to handle. They need fish that are swimming close to the surface. They can plunge but they can’t swim underwater like a shearwater or a puffin would do. When anchovies are here, they’re commonly feeding on those.

What other kinds of terns make an appearance around here?

The less common terns include black terns, least terns, arctic terns and, ironically, common terns. Arctic terns have the record for the longest distance migration; they go practically pole to pole. But you rarely see them—they migrate pretty far offshore.

I didn’t get to tell you about the babies. Tern babies are pretty cute too—camouflaged like gull chicks. The babies stay put out there onthe salt flats, where there’s good visibility and safety from predators, especially if it’s not connected to the mainland, if it’s cut off by water from land. And they tend to nest colonially also, which helps for defense, because they put up a hell of a ruckus. If a predator goes out they’ll dive-bomb ‘em. It’s pretty effective for a predator to be screamed at and dive-bombed by a whole colony.

I saw a baby Caspian tern begging for food and it had a gape almost as big as its whole body—this great big huge mouth! The bills look small, but the jaws attach way toward the back, so the bill can open up a lot larger than you’d think it could.

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