Nature Blog

Groove-billed Ani 1000

The Groove-billed Ani is not a very pretty bird. The bare skin on the face, the huge bill, and the dull, dark plumage give them the look of a miniature vulture. In Costa Rica, they are called “zopilotillos,” the diminutive of “zopilote” which is Spanish for vulture. Robert Benson photo.

The Black Bird That Is Not a Blackbird!

A summer rain always seems to bring out the birds.  After a thunderstorm earlier this week, we set out for a leisurely drive around northern Bee County, just to see what we could see.

It only took me a second to realize that the black bird perched on top of the Huisache was odd.  So odd, we backed up slowly to get a second look.

The odd bird did not fly away; it just quietly remained clinging to the thin branch as it waved in the wind.  We had time for a good long look.  It perched upright but its long tail canted slightly to the left.  Its face was black but bare of feathers.  But it was the bill that really drew our attention:  It was “huge!”

The bill was not only large but it arched strongly upward from its face.  It resembled a big black triangle stuck on the front of the bird.  When the bird turned its face toward us, we could see that the bill was actually quite narrow from side to side.  The bird books describe the beak as “laterally compressed.”  We were close enough to see that the upper mandible of the bill was marked with several deep grooves.

No doubt about it, we were looking at a Groove-billed Ani.   The ani (pronounced “ah-knee”) is a very special bird.  It breeds primarily in South Texas but it wanders up the Texas coast and into Louisiana during the winter months.  Vagrants occur in many other states, however.  There is even one record of a Groove-billed Ani in Nova Scotia, Canada!

However, the Groove-billed Ani is essentially a tropical bird.  Its range extends south through Mexico, Central America, and into the northern part of South America.  In most of their range, anis prefer the open habitat of agricultural areas.  They forage for insects in tall grass, along the branches of small trees, and at the feet of cattle.  In South Texas, we usually see anis around patches of thorny brush.

In appearance, anis are not particularly attractive birds.  Alexander Skutch, who spent years in the tropics studying birds, wrote this about anis:  “With the exception of the vultures, they are the least comely of birds I know…In facial expression they are especially unfortunate.  The Groove-billed Ani’s black bill is narrow and very high, with the upper mandible strongly arched and furrowed lengthwise by parallel curved ridges and channels.  Its black face is largely bare of feathers and prominent lashes shade its dark, beady eyes.”

Sadly, the poor ani is not endowed with a beautiful voice either.  Its call-note, PEE-oh, usually uttered “thrice together in a soft, high-pitched voice, neither unpleasant nor particularly delightful,” is often preceded by a few throaty clucks.  The Groove-billed Ani is not a songbird, but a member of the Cuculiformes, or cuckoo family.  You may be familiar with the roadrunner’s call:  a series of soft “coos” lowering in pitch at the end.  Yellow-billed Cuckoos make a series of hard, guttural “ku-ku-kus” followed by a few slower, softer “kddowl” notes.

Yes, roadrunners are cuckoos, too. The cuckoo family shares similar vocalizations and anatomical features.  Cuckoos, in general, have elongated bodies and rather long, loosely attached tails.  Their feet have two toes pointing forward and two pointing backwards.  Most cuckoos have a weak flight, mostly going from perch to perch, with a few flaps followed by a long glide.  The long tails help with balance on landing.

The Groove-billed Ani has a distinctive flight pattern.  In fact, this alone is enough to distinguish an ani from a Great-tailed Grackle.  Oberholser in The Bird Life of Texas (1972) said:  “The ani jumps into the air from a thorny bush, gives a few quick flaps, then sails for two feet or more, gives another burst of quick flaps, then sails, etc.  Upon arriving at the next bush, the bird lands, at which time the long, loose tail flops forward over the bird’s back—sometimes almost toppling said ani off its perch.”

Closeness 1000

These two Groove-billed Anis demonstrate the affectionate nature of this species. Almost always found in small groups, anis are highly social. It common to see them pressed up against each other even if there is plenty of room!

What the ani lacks in beauty, voice, and grace, it makes up for in other ways.  Skutch opines that they “have been endowed by nature with an extraordinarily affectionate disposition… Few birds crave the company of their own kind more constantly than anis.  I have never seen them quarrel or fight.  When one is separated from its flock, it calls and calls until it finds its companions.  Even in hot weather, when there is no need to huddle together for warmth, two, three, or more perch side by side as closely as they can press…carefully billing and nibbling at each other’s feathers.”

The nesting habits of the Groove-billed Ani are of great interest, particularly to ornithologists.  Anis are so social that they lack a sense of territoriality.  In most species, a breeding pair chases off any others of its kind, maintaining a feeding territory around its nest.  Not so with anis; they welcome company even going so far as to set up a communal nest.  Two or three mated pairs will work together to build a bowl-shaped nest of twigs, usually in a citrus or other thorny tree.  All the females lay eggs in the same nest.  A communal nest can easily have up to 12 eggs in it.  The adults share the incubation duties, willingly popping off and on the nest every few minutes. At each shift exchange, the incoming bird brings a fresh green leaf to add to the lining of the nest.  The bird tucks the leaf under the eggs.  The birds never remove the older leaves, so by the time the eggs hatch, there is a sizable pile of dead leaves in the bottom of the cup.  A male ani is solely in charge of the night shift, while the rest of the group roosts in another tree.

When the chicks hatch, all the adults share in the feeding of the hungry nestlings.  They forage steadily for grasshoppers, other insects, sometimes a lizard, or rarely a berry.   The attendants at one communal nest brought 66 food items to their eight nestlings in two hours, averaging 4.1 meals per chick per hour!

Not surprisingly, the naked and blind chicks grow fast.  At six days of age, they sprout pin-feathers giving them a spiky look.  Within 24 hours the feathers have grown out of the spiky sheathes.  The youngsters begin to resemble their parents and start hopping around the tree often before they are a week old!

Groove-billed Anis stay in happy little groups year-round.  These are not just families but their friends as well.  They perch, preen, forage, and roost together.  You almost never see just one ani.

Which makes me wonder:  where were our ani’s friends?

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