The Rufous-tailed]acamar

Jack Clinton-Eitniear

Abstract


A narrow dirt path leads to one of Belize's most popular places for birdwatching and bathing-the blue hole located along the Hummingbird Highway. The blue hole itself is a pool of cool, fresh water that enters the surface after winding through countless subterranean caves. This tropical pool not only provides humans with a place to cool off from the hot Belizean sun but attracts thousands of insects which are the food of the small, long billed topic of this article.

The rufous-tailed jacamar (Galbula ruficada) is one of fifteen jacamars that inhabit the American tropics from Mexico to Brazil. The most northerly form is the rufous-tailed, being ten inches in length, mainly bill. Its Latin name gives a few clues as to its coloration as the Latin (rufus) means red, ruddy and (cauda) denotes tail. In addition to its rufous belly and tail, the metallic green relative of the woodpecker has a white (male) or tawny (female) throat patch. Your first impression will undoubtedly be of its large, hummingbird-like bill. Spanishspeaking natives were also impressed with its length naming the bird Pico Largo (large bill).

On my first trip to the blue hole I discovered the jacamar displaying its classical behavior of perching on a narrow limb, which often hangs only feet above the water, then, with the energy of a giant hummingbird, dart out to capture a dragonfly or colorful butterfly. After watching several bouts of this behavior my eyes were attracted to some foliage in a nearby tree. Nesting among the mass of leaves and vines was a gray-headed tanager (Eucornetis penicillata). The remainder of my visit was spent observing and photographing the tanager.

Several days later I happened to be talking with a member of the zoo staff when the discussion changed to the blue hole. Mentioning that one could observe the nest of a gray-headed tanager near the path, construction of a royal flycatcher's nest above the pool, and observe the ever present rufoustailed jacamar he responded, "And the jacamar is nesting below the path, too!" After hearing this I decided that another trip to the blue hole was warranted.

The following morning we loaded up the jeep and wound our way down the Hummingbird Highway back to the blue hole. Upon arriving it was an easy matter to discover the location of the ja camars nest. We simply walked down the path, waited at the bottom, and watched the perching jacamar. With an insect in its bill it appeared obviously disturbed at our presence, emitting several high pitched whistles. Then, as if accepting our presence, it flew down to a burrow below the path and proceeded to feed the insect to one of its three chicks.

It appears, after a quick glance at the literature, that our nest site is fairly typical for the species. In addition to nesting along riverbanks and moist hillsides, the jacamar has been documented as using termite nests for breeding purposes. In such situations the birds most likely take over a deserted nest of some termite-dwelling trogon or conure.

When considering the fragile nature of the species I would guess that its nest. was either a tight knit cup, like that of a hummingbird, or a complex woven structure similar to that of a flycatcher. The reality of the matter is that we should compare the jacamar to a miniature kingfisher (although they are not related taxonomically). Jacamars dig their burrows through a combined use of bill and feet; prying sod loose with the bill, then "kicking" it out of the burrow with the feet. The end result is far less impressive than that of the motmot, for instance, whose burrow is many feet in length, but is rather typically two inches in diameter and 17 inches in length. Our specimen appeared less ambitious than normal as its burrow was a meager 13 inches in length although the front appeared to have been disturbed and the burrow might have been a bit longer originally.

Since the jacamars were already feeding their young, little could be recorded as to incubation period and behavior. The literature states that the incubation period is from 19-23 days in length. The female incubates throughout the night then alternates with the male during the day, each one sitting from an hour and a half up to three hours.

Both parents bring food to their young but the male provides significantly more than the female. The point was well illustrated while we watched as the male arrived four times more often than the female. Observations in Costa Rica by Alexander Skutch documented 88 trips made by the male for every 34 by the female. These observations were made during a 2 5 hour period of time which further illustrates the frequency at which the young birds are fed.

Several days later I was driving along a dirt road deep within the Belizean hardwood forest when I stopped to identify the occupants of a large stick nest. Without leaving the vehicle I noticed a bird perched on a branch overhanging the roadway. It was my friend, the rufous-tailed jacamar. Despite the obviously dangerous placement of its nest (it often falls prey to snakes, coatis and man) the species survives to add its metallic green glow to the lush tropical forest. •

 

 


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