Habitat use by threatened vertebrates of the South Atlantic Coast: Olrog’s gull and the meadow lizard
One of the primary processes that affect marine coastal areas is urban development, and the anthropogenic activities it brings such as industry and tourism. The Argentine Pampean coastal region is characterized by a concentration of such activities and consequently is an area of high user conflict. This region is also used by a large number of threatened vertebrate species such as the Olrog’s gull Larus atlanticus and the meadow lizard Liolaemus multimaculatus.
To effectively conserve these species it is essential to determine their distributions and habitat use patterns. The objective of this study was to determine these aspects by deploying radio transmitter and GPS instruments on lizards and gulls, respectively. Researchers collected a total of 305 recordings for gulls, which remained in a 4 km2 area at the mouth of Mar Chiquita Lagoon. This area corresponds to tidal flats densely populated by crabs and frequented by recreational fishermen. The association between gulls and recreational fishing activities may introduce a related risk of death or injury. With respect to lizards, 24 animals were tagged with radio transmitters. Those tagged in human modified habitat demonstrated a home range 57% smaller than those tagged in natural habitat. Lizards were observed exclusively in parcels that were predominantly dune habitat with minimal native plant cover and where the exotic tree species A. longifolia was practically absent.
The results for both species suggest that specific recommendations should be developed to reduce impacts generated by human activities both from the point of view of recreational fisheries for gulls and habitat modification for lizards. The project also included outreach and education activities in local primary schools with the aim of raising awareness about conservation issues and anthropogenic pressures related to key species along the Buenos Aires coast. ($9,240)