The Tropical Screech Owl (Megascops choliba) is a small species of owl

Owl

Owls are a group of birds that belong to the order Strigiformes, constituting 200 bird of prey species. Most are solitary and nocturnal, with some exceptions . Owls hunt mostly small mammals, insects, and other birds, although a few species specialize in hunting fish...

 in the Strigidae family.

Range and habitat

It is found throughout South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 (including Trinidad and Tobago

Trinidad and Tobago

Trinidad and Tobago officially the Republic of Trinidad and Tobago is an archipelagic state in the southern Caribbean, lying just off the coast of northeastern Venezuela and south of Grenada in the Lesser Antilles...

), except in the Andes

Andes

The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...

, the arid Pacific lowlands, and the far south. Its distribution also extends into southern Central America

Central America

Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

 in Costa Rica

Costa Rica

Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....

 and Panama

Panama

Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...

. It is generally common – in large parts of its range among the most common species of owls and likely the most common screech owl of the tropics. It occurs in a wide range of wooded habitats, ranging from arid Caatinga

Caatinga

Caatinga is a type of vegetation, and an ecoregion characterized by this vegetation in the northeastern part of Brazil. The name "Caatinga" is a Tupi word meaning "white forest" or "white vegetation"...

to dense rainforest

Rainforest

Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...

, and even city parks.

Description

This polymorphic

Polymorphism (biology)

Polymorphism in biology occurs when two or more clearly different phenotypes exist in the same population of a species — in other words, the occurrence of more than one form or morph...

 species is highly variable in colour, it being overall grey-brown or (less commonly) brown or rufous

Rufous

Rufous is a colour that may be described as reddish-brown or brownish-red, as of rust or oxidised iron.The first recorded use of rufous as a colour name in English was in the year 1782....

, but always with a relatively distinctive blackish edge to the face and yellow irides

Iris (anatomy)

The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupils and thus the amount of light reaching the retina. "Eye color" is the color of the iris, which can be green, blue, or brown. In some cases it can be hazel , grey, violet, or even pink...

. The length is 21–23 cm (8.3–9 in) long and weigh is 97-160 grams (3.4-5.7 oz).

Subspecies

M. c. choliba (Vieillot 1817): Occurs in southern Mato Grosso and São Paulo, Brazil, south to eastern Paraguay.

M. c. luctisomus (Bangs and Pernard 1921): Occurs from the Pacific slope in Costa Rica south to the Canal Zone in Panama, and on the Pearl Islands.

M. c. margaritae (Cory 1915): Restricted to Margarita Island off of northern Venezuela. Paler than nominate choliba.

M. c. crucigerus (Spix 1824): Occurs from eastern Colombia, Venezuela, and Trinidad east to the Guianas and south to eastern Peru. Body feathers have fluffy yellowish spots.

M. c. duidae (Chapman 1929): Confined to upper forested slopes of Mount Duida and Mount Neblina in southern Venezuela. This is a very dark subspecies with a rather uniform crown and a broken, whitish, collar on hindneck; this is the only subspecies of Tropical Screech Owl with a white band across that back of the neck. Perhaps represents a separate species.

M. c. decussatus (Lichtenstein 1823): Occurs in central and southern Brazil. Smaller and paler than crucigerus, with whitish spots on the mantle.

M. c. uruguaiensis (Hekstra 1982): Occurs in southeastern Brazil (Santa Catarina, Rio Grande do Sul), northeastern Argentina and in Uruguay. Shaft streaks on underparts are rather prominent; body feathers with buffy-rufous downs.

M. c. surutus (L. Kelso 1941): Found in Bolivia. Brighter rufous than crucigerus, and the streaks and bars are more reduced.

M. c. wetmorei (Brodkorb 1937): Occurs in the chaco of Paraguay and Argentina, south to Mendoza and northernf Buenos Aires. Darker than decussatus and underparts more dirty-buff.

Feeding

The Tropical Screech Owl forages from a low level perch and captures prey on the ground, branches, or on wing. This species primarily preys on large arthropod

Arthropod

An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...

s, comprising about 66% of prey, and small vertebrate

Vertebrate

Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...

s, comprising about 33%. Known invertebrate prey has included earthworm

Earthworm

Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...

s, scorpion

Scorpion

Scorpions are predatory arthropod animals of the order Scorpiones within the class Arachnida. They have eight legs and are easily recognized by the pair of grasping claws and the narrow, segmented tail, often carried in a characteristic forward curve over the back, ending with a venomous stinger...

s, spider

Spider

Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...

s, harvestmen, and a wide variety of insects, including roaches

Blattidae

The Blattidae is a family of the order Blattaria . It contains several of the most common household cockroaches.-Selected species:*Oriental cockroach *American cockroach...

, termites

Termitidae

Termitidae is a family of termite, containing the following subfamilies:*Apicotermitinae Grassé & Noirot, 1955*Foraminitermitinae Holmgren, 1912*Macrotermitinae Kemner, 1934*Nasutitermitinae Hare, 1937*Sphaerotermitinae Engel & Krishna, 2004...

, grasshoppers

Acrididae

The Acrididae are the predominant family of grasshoppers, comprising some 10,000 of the 11,000 species of the entire suborder Caelifera. The Acrididae are best known because all locusts are of the Acrididae. The subfamily Oedipodinae is sometimes classified as a distinct family Oedipodidae in the...

, katydids

Tettigoniidae

The family Tettigoniidae, known in American English as katydids and in British English as bush-crickets, contains more than 6,400 species. It is part of the suborder Ensifera and the only family in the superfamily Tettigonioidea. They are also known as long-horned grasshoppers, although they are...

, raspy crickets

Gryllacrididae

Gryllacrididae are a family of non-jumping cricket-like insects occurring worldwide, known commonly as "leaf-rolling crickets" or "raspy crickets". The family historically has been broadly defined to include what are presently several other families, such as Stenopelmatidae and Rhaphidophoridae ,...

, crickets, mole crickets, mantids and various beetle

Beetle

Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...

s, moth

Moth

A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

, caterpillar

Caterpillar

Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...

s and ants. Known vertebrate prey has included small frogs, small snake

Snake

Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...

s, bird

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s, opossums

Gracilinanus

Gracilinanus is a genus of opossum in the family Didelphidae. It was separated from the genus Marmosa in 1989, and has since had the genus Cryptonanus removed from it...

, bat

Bat

Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...

s and various rodent

Rodent

Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

s.

Reproduction

Males usually start singing in August or early September. Courtship mostly occurs in September. Males advertise possible nesting sites to females by flying to them and singing from the entrance. The clutch of 1 to 3 eggs (sometimes 6) are typically laid directly in natural cavities, abandoned bird nests, nest boxes, old woodpecker holes or even rotted-out fence posts. If feeling threatened during brooding, they will throw themselves flat on their back over the nestlings and extend their claws toward the intruder. In flight, they also will strike humans with their claws.

The Tropical Screech Owl chicks are covered with white down, sparser on the dorsal area and their legs and feet were pale pink. The bill is pearl gray and has a white egg tooth. The nestlings eyes are closed at birth, but begin to open by the 6th day, and may not become fully open until the 10th day. Fledging occurs around 1 month of age.