Join for FREE
It only takes a minute!
Zeiss - Always on the lookout for something special – Shop now

Welcome to BirdForum.
BirdForum is the net's largest birding community, dedicated to wild birds and birding, and is absolutely FREE! You are most welcome to register for an account, which allows you to take part in lively discussions in the forum, post your pictures in the gallery and more.

Personal tools
Main Categories

Shiny Cowbird

From Opus

This article is incomplete.
This article is missing one or more sections. You can help the BirdForum Opus by expanding it.

MalePhoto by Steve GAsa Wright Centre, Trinidad.(Picture shows a bird much bluer than I have ever seen, possibly due to special light effects; use the gallery link below to see the variation in this species)
Photo by Steve G
Asa Wright Centre, Trinidad.
(Picture shows a bird much bluer than I have ever seen, possibly due to special light effects; use the gallery link below to see the variation in this species)
Molothrus bonariensis


[edit] Identification

Male: Shiny black with purple gloss, conical bill (See note under picture)
Female: Grayish brown upperside, lighter brown underside with slight spotting, faint supercilium
Eyes dark brown.

[edit] Similar Species

Carib Grackle differs in having pale eye and keel-shaped tail, where tail of Shiny Cowbird is flat

[edit] Distribution

Found from south east USA through the Caribbean and South America to Argentina. The spread north from South America started around 1900 and is still ongoing.

Strangely, the species initially did not become established in or completely circumvented some of the islands in the Lesser Antilles including e.g., Dominica, where it is only now starting to appear in numbers (2011-2012).

FemalePhoto by njlarsenCongo Rd Shooting Swamp,  Barbados, 5 January 2013
Photo by njlarsen
Congo Rd Shooting Swamp, Barbados, 5 January 2013

[edit] Taxonomy

[edit] Subspecies

Seven subspecies are found within the range[1]. M.b. minimus is the form that has spread north.

  • M. b. minimus
  • M. b. cabanisii
  • M. b. venezuelensis
  • M. b. aequatorialis
  • M. b. occidentalis
  • M. b. riparius
  • M. b. bonariensis

[edit] Habitat

Favours open areas, mostly at lower elevations (at least in the Caribbean)

[edit] Behaviour

This species engages in nest parasitism where the female lays its eggs in the nest of other birds, with 250 different species known to have had eggs placed in their nest and almost 100 of these known to have raised young of Shiny Cowbird. In the Caribbean, there seems to be a preference for members of the icterids such as orioles and blackbirds, but in southern South America many different groups of birds are among the known hosts. Shiny Cowbird has caused a decline in several species, and is one of the reasons that the Yellow-shouldered Blackbird is endangered. During egg laying, it is common that Shiny Cowbird puncture or remove at least one host-species egg from the nest.

[edit] References

  1. Clements, JF. 2011. The Clements Checklist of Birds of the World. 6th ed., with updates to August 2011. Ithaca: Cornell Univ. Press. ISBN 978-0801445019. Spreadsheet available at
  2. Neotropical Birds Online

[edit] External Links


Fatbirder's Top 1000 Birding Websites

Help support BirdForum

Page generated in 0.36373210 seconds with 8 queries
All times are GMT. The time now is 18:28.