River otters reclaiming place across the state
By SHANNON TOMPKINS Copyright 2010 Houston Chronicle
March 13, 2010, 8:06PM

Most Texans have never seen a wild river otter, and they are the poorer for it.

Even those who spend a lot of time outdoors rarely catch a glimpse of these sleek, secretive, amazingly animated aquatic members of the weasel family. Some who have spent years afield have never had the pleasure — and it is a pleasure.

“Consider yourself lucky if you see an otter,” said Gary Calkins.

It's not that there aren't a fair number of otters in Texas — although there are no dependable estimates of how many of these 15-25-pound physical manifestations of healthy waterways and wetlands roam the state or how much of Texas otters call home.

It's that otters prefer to live in wet, wild places where humans are simply occasional visitors, and they are most active — hunting fish, crawfish, frogs, snakes and other forage with what can appear an electric mix of exuberance and joy — in the half-light of dawn and dusk.

Unlike some wildlife such as raccoons, possums, coyotes and deer, which readily adapt to living in proximity to humans, otters demand their space. And like all high-end predators with sizable home ranges, otters are never numerous even in the best of habitats.

“If you're a duck hunter, you've got a good chance of seeing otters,” Calkins said. “Otherwise, you just about have to be at the right place at the right time.”

He would know. Calkins, a Jasper-based district biologist for Texas Parks and Wildlife Department's wildlife division, has considerable personal and professional experience with these animals, having raised orphaned baby river otters.

“They have no clue how strong they are — all muscle — and they are so playful. But they're ... intense,” Calkins said.

Calkins also is deeply involved in trying to add to the relatively thin store of knowledge about river otters' behavior and population status in Texas.

Healthy indication
Calkins is gathering information aimed at mapping river otters' current range in Texas and developing methods of gauging and monitoring their population.

Such knowledge is crucial because the web-footed weasels' lives depend on healthy wetland ecosystems, terrestrial and aquatic.

“They are an indicator species,” Calkins said. “If otters are doing well in an area, it generally means the system is in pretty good shape.”

Even more important, otters are part of Texas' natural heritage and have tangible and intangible value. Texas is a better place with otters in it — just ask anyone who has seen one.

Any management decisions aimed at maintaining otters in Texas will have to be based on best-available knowledge. And best-available knowledge isn't very robust, just now.

Much of the information available on Texas river otters — population status, especially — is outdated. And information on otter densities — how many otters typically live in X acres of habitat — is almost nonexistent.

On the comeback trail
According to historical reports, river otters originally ranged across most of the eastern half of Texas and even into the Panhandle. The animals were — and are — inexorably tied to rivers, creeks, bayous and other waterways.

But by the 1960s, when the most recent substantial assessment of the otter population was rendered, a combination of factors — chiefly habitat loss or degradation, unregulated hunting and trapping — had greatly contracted otter range and abundance.

“The studies in the '60s have otters confined to the far-eastern part of the state — the Sabine, Neches and Trinity drainages,” Calkins said.

But since then, it appears otters have been reclaiming some of their range.

For the past few years, Calkins has been soliciting and compiling information on reliable otter sightings across the state. The results indicate otters are much more widespread than they were just a few decades ago.

Predictably, most of the otter reports are from waterway-rich eastern Texas. But some have come from much farther afield.

Calkins has received verified or reliable reports of otter sightings from the lower Guadalupe River drainage (Gonzales, Victoria), as far west as the Llano River and as far northwest as Henrietta, near Wichita Falls.

“It could reflect a resurgence,” he said.

A difficult task
Mapping otter range will prove easier than determining otter densities, individual/family home ranges and mortality rates. Traditional wildlife research methods for gaining such information — live-trapping animals, fitting them with a radio collar and monitoring their movements — prove difficult with otters.

“Otters are really hard to live-trap, and because of their body shape and size, it's hard to fit them with radio transmitters,” Calkins said.

Also, because some otters travel amazingly long distances, radio-tracking requires use of expensive satellite transmitter collars instead of the less costly, limited-range VHF collars.

While otters present challenges for researchers, better understanding these charismatic creatures could help ensure they remain part of the fabric of Texas' natural world.

And as anyone who has had the magical experience of watching wild otters will affirm, that's a hugely worthwhile goal.

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