tricolored blackbird (Agelaius tricolor)

Candidate Info | Federal Register | Conservation Plans | Petitions | Life History

Listing Status:   

General Information

The Tricolored Blackbird is a medium-sized (18-24cm total length), sexually dimorphic North American passerine (Beedy, Edward, and Hamilton III 1999). Adult males are typically larger than females, and are black with bright red and white plumage on the wing shoulder. Adult females have sooty brown-black plumage with distinct grayish streaks, a relatively white chin and throat, and a smaller reddish shoulder-patch. Banding studies indicate a lifespan of 12-13 years (DeHaven and Neff 1973, Kennard 1975).

Citations:

  • Beedy, Edward C. and William J. Hamilton III. 1999. Tricolored Blackbird (Agelaius tricolor), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/423
  • Beedy, E. C. and W. J. Hamilton III. 1997. Tricolored Blackbird status update and management guidelines. September. (Jones & Stokes Associates, Inc. 97-099.) Sacramento, CA. Prepared for U.S. Fish and Wildlife Serv., Portland, OR, and Calif. Dept. of Fish and Game, Sacramento, CA.
  • Collier, G. 1968. Annual cycle and behavioral relationships in the Red-winged and Tricolored Blackbirds of southern California. Phd Thesis. Univ. of California, Los Angeles.
  • Dehaven, R. W. and J. A. Neff. 1973. Recoveries and returns of Tricolored Blackbirds, 1941-1964. West. Bird Bander 48:10-11.
  • Dehaven, R. W. 1975. Plumages of the Tricolored Blackbird. West. Bird Bander 50:59-61.
  • Emlen, J. T. 1941. An experimental analysis of the breeding cycle of the Tricolored Red-wing. Condor 43:209-219.
  • Kennard, J. H. 1975. Longevity records of North American birds. Bird-Banding 46:55-73.
  • Martin, A. C., H. S. Zim, and A. L. Nelson. 1951. American wildlife and plants: a guide to wildlife food habits. McGraw-Hill, New York.
  • Neff, J. A. 1942. Migration of the Tricolored Red-wing in central California. Condor 44:45-53.
  • Orians, G. H. 1960. Autumnal breeding in the Tricolored Blackbird. Auk. 77:379-398.
  • Orians, G. H. 1961b. Social stimulation within blackbird colonies. Condor 63:330-337.
  • Orians, G. H. 1985. Blackbirds of the Americas. Univ. of Washington Press, Seattle.
  • Payne, R. 1969. Breeding seasons and reproductive physiology of Tricolored Blackbirds and Redwinged Blackbirds. Univ. Calif. Publ. Zool. 90:1-137.
  • Pyle, P. 1997. Identification guide to North American birds, Part I. Slate Creek Press, Bolinas, CA.
  • Skorupa, J. P., R. L. Hothem, and R. W. DeHaven. 1980. Foods of breeding Tricolored Blackbirds in agricultural areas of Merced County, California. Condor 82:465-467.

  • States/US Territories in which the tricolored blackbird, Wherever found is known to or is believed to occur:  California , Nevada , Oregon
  • US Counties in which the tricolored blackbird, Wherever found is known to or is believed to occur:  View All
  • Countries in which the the tricolored blackbird, Wherever found is known to occur:  Mexico
  • Additional species information
 
Current Listing Status Summary
Status Date Listed Lead Region Where Listed
Pacific Region (Region 1) Wherever found

» Candidate Information

Candidate Notice of Review Documents
Date Citation Page Title
1982-12-30 Review of Vertebrate Wildlife for Listing as End. or Thr. Species
1985-09-18 Review of Vertebrate Wildlife; Notice of Review; 50 FR 37958-37967
1989-01-06 ETWP; Animal Notice of Review; 54 FR 554 579
1991-11-21 ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species; 56 FR 58804 58836
1994-11-15 ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species.

» Federal Register Documents

Federal Register Documents
Date Citation Page Title
2015-09-18 00:00:00.0 80 FR 56423 56432 Endangered and Threatened Wildlife and Plants; 90-Day Findings on 25 Petitions
2004-06-04 00:00:00.0 69 FR 31632 31635 Availability of the Final Environmental Impact Statement/Environmental Impact Report for an Incidental Take Permit for the Multiple Habitat Consrevation Program, Carlsbad, CA
1994-11-15 00:00:00.0 59 FR 58982 59028 ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species.
2005-09-02 00:00:00.0 70 FR 52434 52436 Notice of Availability of a Draft Environmental Impact Statement/Environmental Impact Report and Receipt of an Application for an Incidental Take Permit for the East Contra Costa County Habitat Conservation Plan and Natural Community Conservation Plan, Contra Costa County, CA
1982-12-30 00:00:00.0 47 FR 58454 58460 Review of Vertebrate Wildlife for Listing as End. or Thr. Species
2002-11-04 00:00:00.0 67 FR 67209 67210 Fish and Wildlife Service, Interior:Draft Environmental Impact Report/Environmental Impact Statement and Habitat Conservation Plan for the Natomas Basin, Sacramento County, CA; Extension of comment period and notice of availability.
2005-03-14 00:00:00.0 70 FR 12497 12498 Preparation of an Environmental Impact Statement for the North County Multiple Species Conservation Program, San Diego, CA
1985-09-18 00:00:00.0 50 FR 37958 37967 Review of Vertebrate Wildlife; Notice of Review; 50 FR 37958-37967
2013-11-04 00:00:00.0 78 FR 66058 66061 Habitat Conservation Plan for South Sacramento County, California
1991-11-21 00:00:00.0 56 FR 58804 58836 ETWP; Animal Candidate Review for Listing as Endangered or Threatened Species; 56 FR 58804 58836
2006-12-05 00:00:00.0 71 FR 70483 70492 90-Day Finding on a Petition To List the Tricolored Blackbird as Threatened or Endangered
1989-01-06 00:00:00.0 54 FR 554 579 ETWP; Animal Notice of Review; 54 FR 554 579

» Conservation Plans

Habitat Conservation Plans (HCP) (learn more)
HCP Plan Summaries
East Contra Costa County HCP/NCCP
Fieldstone/La Costa & City of Carlsbad
Kern Water Bank
Lake Mathews
MHCP, City of Carlsbad Habitat Management Plan
MSCP, City of Chula Vista Subarea Plan
MSCP, City of La Mesa Subarea Plan
MSCP, City of Poway Subarea Plan
MSCP, City of San Diego Subarea Plan
MSCP, County of San Diego Subarea Plan
Natomas Basin, Metro Air Park
Natomas Basin Revised HCP and Litigation Resolution - City of Sacramento, Sutter County, and Natomas Basin Conservancy
North Peak Development Project
Orange County Southern Subregion NCCP/HCP
PG&E San Joaquin Valley Operations & Maintenance HCP
San Diego Gas & Electric
San Joaquin County Multi-Species Habitat Conservation and Open Space Plan
Santa Clara Valley HCP/NCCP
Western Riverside MSHCP (One permit w/ 22 permittees)

» Petitions

» Life History

Habitat Requirements

Breeding colonies require a nearby source of water, suitable nesting substrate, and natural grassland, woodland, or agricultural cropland biomes in which to forage. Historically, breeding colonies had been strongly associated with emergent marshes, but more recently there has been a shift to non-natively vegetated and active agricultural areas. In the time interval of 1931-1936, 93% of breeding colonies were observed in freshwater marshland habitats dominated by cattails and bulrushes (Neff 1937). In 1994, 55% of all observed breeding colonies were associated with dairy farms as they contain all required resources (Hamilton et al. 1995).

Food Habits

Tricolored Blackbirds are opportunistic foragers and will consume any locally abundant food resources, including grasshoppers and many other insects, rice, grains, watergrass, snails, and small clams (Collier 1968, Martin et al. 1951, Skorupa et al. 1980). High quality foraging areas include habitats such as irrigated pastures, lightly grazed rangelands, dry seasonal pools, mowed alfalfa fields, feedlots and dairy farms (Breedy and Hamilton 1997). Like other blackbirds, the tricolored Blackbird uses its bill to expose insects hidden under rocks, within agricultural plants, or under soil and sticks (Orians 1985). Individuals will often forage in deep dense grasses and other vegetation, and will occasionally fly-catch up to 30m above breeding colonies (Beedy, Edward, and Hamilton III 1999).

Movement / Home Range

The Central Valley and surrounding foothills of California is home to over 99% of the Tricolored Blackbird populations, though breeding sites can also be found scattered throughout Oregon, Washington and Nevada (Beedy, Edward, and Hamilton III 1999). Banding studies have shown that some Tricolored Blackbird individuals will reside in Central Valley throughout the year (Neff 1942, DeHaven and Neff 1973) whereas other individuals will migrate from their first nesting sites in the San Joaquin Valley to a second nesting site located in more Northern regions, such as the Sacramento Valley, northeast California, and southern Oregon (though sightings in Oregon are rare) (Beedy and Hamilton 1997). Winter distribution and movements indicate winter turnover and mobility at roost sites; however this requires further study (Collier 1968).

Reproductive Strategy

Tricolored Blackbirds form the largest breeding colonies of any North American passerine, and an individual breeding colony at a single site can be made up of thousands of birds. The species is polygamous; males defend small territories within these breeding colonies and will mate with 1-4 females (Beedy, Edward, and Hamilton III 1999). Tricolored Blackbirds are itinerant breeders, meaning they will nest multiple times in multiple locations throughout the breeding season and may rear 2 or more broods in a year. The timing of breeding colony development will vary depending on the geographical location of the population, however all breeding is usually completed by late June to early August (Orians 1960, Payne 1969). Clutch size is typically 3-4 eggs but can vary from 1-5, and the estimated incubation period is 11-12 days (Payne 1969, Emlen 1941, Orians 1961b). Young are altricial at birth, hatching from the egg blind, largely naked, and with poor coordination; the young are dependent on parents until they are about 25 days old (Payne 1969).

» Other Resources

NatureServe Explorer Species Reports -- NatureServe Explorer is a source for authoritative conservation information on more than 50,000 plants, animals and ecological communtities of the U.S and Canada. NatureServe Explorer provides in-depth information on rare and endangered species, but includes common plants and animals too. NatureServe Explorer is a product of NatureServe in collaboration with the Natural Heritage Network.

ITIS Reports -- ITIS (the Integrated Taxonomic Information System) is a source for authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.

FWS Digital Media Library -- The U.S. Fish and Wildlife Service's National Digital Library is a searchable collection of selected images, historical artifacts, audio clips, publications, and video.