The triciolored blackbird is federally protected under the Migratory Bird Treaty Act, or MBTA (https://www.fws.gov/migratorybirds/RegulationsPolicies/mbta/mbtintro.html) and Endangered under the California Endangered Species Act.
Formerly, the tricolored blackbird was exempt from the protections offered to many North American birds by the Migratory Bird Treaty Act, as most blackbirds and relatives ("yellow-headed red-winged, rusty, and Brewer's blackbirds, cowbirds, all grackles, crows, and magpies") are considered potential agricultural pests and exceptions to protection under the MBTA are possible in cases where birds are about to cause depredations "to ornamental or shade trees, agricultural crops, livestock, or wildlife, or when concentrated in such numbers and manner as to constitute a health hazard or other nuisance" (50 CFR 21.43). However, in 1985, the tricolored blackbird was removed from the list of exempted species and now is fully protected under the MBTA (50 CFR Part 10 13708).
Currently, the tricolored blackbird is considered a Species of Conservation Concern (http://www.fws.gov/migratorybirds/reports/BCC2002.pdf). As of September 18, 2015, the species' status is under review after a 90 day finding that formal listing on the Endangered Species Act may be warranted.
The tricolored blackbird was given emergency Endangered status under the California Endangered Species Act in December, 2014. This listing provided temporary (6 month) protection but was allowed to expire in June, 2015. The State status of the species is currently (as of September, 2015) being discussed by the California Department of Fish and Wildlife for permanent protection and this page will be updated to reflect any change in State status. See the list of State and Federally Listed Endangered and Threatened Animals of California at:
The Bureau of Land Management designates the tricolored blackbird a Sensitive Species (BLM 2003; http://www.blm.gov/nhp/efoia/nv/ib/2003/nvib2003-097a.pdf).
Not a regulatory agency, the World Conservation Union, or IUCN (http://www.iucn.org/), maintains lists of threatened and endangered species world-wide. The tricolored blackbird was placed on the IUCN Red List as Endangered in 2006 (http://www.iucnredlist.org/details/22724196/0).