The local conservation status of the regionally rarest bird species in the state of Rio de Janeiro, southeastern Brazil

We reviewed the local current status and summarized the suspected causes of rarity,  and presumed  major threats to the 84 rarest bird species in the state of Rio de Janeiro, southeastern Brazil .  We have focused on the bird species that have  not  been  recently  recorded or have fewer than 10 records  in the last five decades in the state of Rio de Janeiro .  Of these, 24 species are considered globally threatened or near threatened, and at least about 30 species are actually common or abundant elsewhere in their distribution.  More than half of these species are forest birds inhabiting mainly lowland forests, but less than one-fifth of these species are endemic to the Atlantic Forest. The trophic guilds with the highest numbers of species were omnivores  and  insectivores . The main habitats  used by  the rarest  bird species  were wetlands,  l owland forest canopy,  secondary forest canopy and secondary forest edge .  Bird species using two or more habitats were more represented among rare species than those using only a single habitat.  Nine species were considered locally extinct, 11 probably Extinct, 27 Critically Endangered and 13  considered Data Deficient in Rio de Janeiro which  are of  increased  conservation concern in the region .  Although included among the rarest birds  found  in the state of Rio de Janeiro ,  24 species  were not  classified as locally threatened because they are naturally rare migrants or vagrants in the region, without evidence of  s ignificant population size reduction in the state in recent decades .  Fifteen species  had their conservation status considered  threatened in the state  for the  first time . Forty-four species  had their  local  conservation status uplisted, while only five species were downlisted.  The major causes of rarity  and threats to these species in the region are h abitat loss and hunting/trapping, but  nearly one - third of them have unknown causes of rarity .