Socorro mockingbird

Appearance

It also has a distinct juvenile plumage, more rufous above and has a heavy pattern, especially below. This uncannily resembles, e.g., the gray thrasher (Toxostoma cinereum) from Baja California, but is apparently a case of convergent evolution.

Range and habitat

The Socorro mockingbird is an endangered mockingbird endemic to Socorro Island in Mexico's Revillagigedo Islands.

It is not believed that the northern mockingbird that has colonized Socorro in the late 20th century is limiting the recovery of its relative. The two Mimus do not occupy the same habitat and even if they did, the native bird is larger and more powerful and would probably simply outcompete its mainland relative in native vegetation at least. The extermination of the sheep is underway in the hope of restoring the island ecosystem.

Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.

Diet and breeding

As late as March 1953 it was still "common" at lower elevations, foraging in arid open shrublands of Croton masonii and prickly pear. The breeding season is extended, with nests in attendance between November and July, with the peak laying occurring in March and April.

In crisis

This species numbers fewer than 400 individuals altogether and is considered Critically Endangered by the IUCN. Socorro mockingbird is mostly threatened by habitat loss caused by feral sheep and the locust Schistocerca piceifrons, and predation by feral cats that became established after 1953, probably in the early 1970s. On the other hand, its terrestrial habits make it vulnerable to cat predation and this may limit its recovery even if sheep are contained. It is not known for example in how far foraging in the lowlands – now cat-ridden – was important for robust breeding success.

In addition, it can be expected that predation on this species by both the native red-tailed hawk as well as the feral cats has increased since the Socorro dove – formerly a preferred prey item – has become extinct in the wild. This threat is not considered significant compared to the problem of introduced species however.

Socorro mockingbird is Critically Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.

Sources

Written for this catalog from the English Wikipedia article on Socorro mockingbird, Wikidata item Q1040304. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.