Black-backed Thornbill Ramphomicron dorsale is endemic to the Santa Marta Mountains of Colombia, where it occurs from 2,000-4,600 m. It is currently classified as Least Concern but its Extent of Occurrence has recently been estimated at 2,600 km2.
Santa Marta Wren Troglodytes monticola is another Santa Marta endemic, found in low, thick shrubbery at the timberline and in sheltered spots high in the páramo zone, from 3,200 to 4,600 m. It is known from collections made in 1922 and from one record in the upper río Frío Valley, at 3,600 m, where a pair was observed and tape-recorded in a small montane forest patch (c.2 ha) amidst heavily burned and overgrazed páramo. It is currently classified as Vulnerable on the IUCN Red List, however its Extent of Occurrence has recently been estimated at 1,300 km2.
Loss of páramo vegetation in the Santa Marta Mountains has been acute – páramo is regularly burned and streamside vegetation is unsustainably cut for firewood (N. Krabbe in litt.).
Both species may now qualify as Endangered under criterion B1a+b if their range is now severely fragmented (having an Extent of Occurrence <5,000 km2 and a continuing decline in at least the Area of Occupancy, area, extent and/or quality of habitat and number of locations or subpopulations, and number of mature individuals).
Comments on this proposal and the status of these species, particularly focusing on the degree of fragmentation, number of locations, and rate of habitat loss, are sought.