MAIISG

Assessment Rationale:

Calathus lundbladi is endemic to Sao Miguel (Azores, Portugal). São Miguel (Azores, Portugal). It has a very small extent of occurrence (EOO = 43 km²) and area of occupancy (AOO = 36 km²). There is a continuing decline in the EOO, AOO, extent and quality of habitat as well as the number of mature individuals as a result of the invasions of non-native plants. The species occurs only at one location. Therefore, we suggest as future measures of conservation: (1) regular monitoring of the species; and (2) control of invasive species namely Hedychium gardnerianum and Clethra arborea. Based upon the small geographic range of the species with only one location and continuing decline of its habitat area and quality, it is assessed as Critically Endangered.

Geographic Range:

Calathus lundbladi is a single island endemic species restricted to S. Miguel (Azores, Portugal) (Borges et al. 2010), known from the Natural Forest Reserve of Pico da Vara (Tronqueira). The extent of occurrence (EOO) is 43 km² and the maximum estimated area of occupancy (AOO) is 36 km². However, the AOO and EOO are probably smaller since the species is possibly considered extinct in Furnas.

Population:

The species is very rare and only known from a single subpopulation. A continuing decline in the number of mature individuals is inferred from monitoring schemes (sampled 1989 with larger populations and decreasing numbers in 2000 and 2010), and from the ongoing habitat degradation due to invasions of alien plants.

Habitat and Ecology

This is closed forest species that occurs in the hyper-humid Azorean native forests, surrounded by plantations of exotic trees (Cryptomeria japonica), with an altitudinal range between 543 and 1000 m. It is a nocturnal predator that lives under barks of native trees and in the soil. The reduction of hind wings imply a low dispersal ability.

Major Threat(s):

In the past, the species has probably strongly declined due to deforestation. The species is considered extinct in Furnas due to major historical land use changes with clearing of original habitat. The most important ongoing threat to this species is the spread of invasive plants (Hedychium gardnerianum and Clethra arborea) that are changing the habitat structure, namely decreasing the cover of bryophytes and ferns in the soil and promoting the spread of other plants. Based on Ferreira et al. (2016) the habitat will decline as a consequence of climate change (increasing number of droughts and habitat shifting and alteration), which may drive this species to extinction, because it is dependent on humid forests.

Conservation Actions

The species is protected by regional law (RAA 2012). Its habitat is in a regionally protected area (S. Miguel Natural Park). The São Miguel Natural Park administration is currently starting control measures of the invasive plants. LIFE PRIOLO project started with a restoration of degraded habitats increasing the area of pristine forest.  A habitat management plan is needed and anticipated to be developed during the coming years. Further research is needed into its ecology and life history in order to obtain information on population size, distribution and trends. A general monitoring scheme for the invertebrate community in the habitat is in place, but the subpopulation of this particular species and its habitat needs to be monitored in more detail in order to contribute to perform an area-based management plan and a species potential recovery plan due to recent rarity. Monitoring every ten years using the BALA protocol will inform about habitat quality (see e.g. Gaspar et al. 2011).