Distance to international border shapes the distribution pattern of the growing Little BustardTetrax tetraxwinter population in Northern Iran

Abstract

SummaryThe Little Bustard Tetrax tetrax is a Near Threatened grassland bird that is fully migratory within its eastern population, wintering in large numbers across the south Caucasus and northern parts of Iran. The species’ habitat selection has been comprehensively studied in its western European range, but very limited information is available for its eastern population. Surveys carried out between 2010 and 2015 show a considerable population increase and probable range expansion in the region. We modelled the suitability of potential winter habitat for the species and found that distance to country border, land cover and altitude were the most important variables in predicting habitat suitability. There is still considerable hunting pressure in Iran and distance to border is likely to be related to strict hunting prohibition along the border belt imposed for military purposes. This represents an opportunity for the conservation of the species, where management efforts should aim at ensuring the maintenance of suitable land cover.

Applying opportunistic observations to model current and future suitability of the Kopet Dagh Mountains for a Near Threatened avian scavenger

“…MaxEnt (Maximum Entropy Modeling) is one of the best methods among many algorithms for modeling species distribution patterns 39–41 and was successfully applied in modeling avian distribution. 42–44 This method only needs presence data from the species and is very effective even when distribution data is scarce. 45 MaxEnt was run with maximum iterations of 1000, convergence threshold of 0.0001 and 1000 background points.…”

An update on the conservation status of the Little Bustard Tetrax tetrax: global and local population estimates, trends, and threats

“…Other winter quarters occur in northern Iran, along the Caspian coast, but also in the north-west, near the Azerbaijani border and the north-east, bordering Turkmenistan and Afghanistan (Yousefi et al 2017), although there are historical observations from more central parts of the country (Sehhatisabet et al 2012). The wintering population in Iran appears to reach c.57,000 individuals (Yousefi et al 2017), and occupies a variety of habitats, including farmland, pastures, and halophytic shrub-steppes (Sehhatisabet et al 2012). As in Azerbaijan, this wintering population seems to have increased steadily in numbers and geographical range in recent times (Yousefi et al 2017), in part presumably due to a hunting ban enforced in 2006-2009 to prevent an avian influenza outbreak (Sehhatisabet et al 2012), although the habitat changes that occurred in Russian and central Asian breeding grounds may have also contributed.…”

“…The wintering population in Iran appears to reach c.57,000 individuals (Yousefi et al 2017), and occupies a variety of habitats, including farmland, pastures, and halophytic shrub-steppes (Sehhatisabet et al 2012). As in Azerbaijan, this wintering population seems to have increased steadily in numbers and geographical range in recent times (Yousefi et al 2017), in part presumably due to a hunting ban enforced in 2006-2009 to prevent an avian influenza outbreak (Sehhatisabet et al 2012), although the habitat changes that occurred in Russian and central Asian breeding grounds may have also contributed. Nevertheless, the area surveyed has increased in Iran (Yousefi et al 2017) and shifts of wintering areas might have occurred due to habitat modification.…”

Environmental predictors for the distribution of the Caspian green lizard, Lacerta strigata Eichwald, 1831, along elevational gradients of the Elburz Mountains in northern Iran

“…Species distribution models (SDMs) are commonly used to predict suitable environmental conditions for species presence or absence (Guisan and Thuiller, 2005;Pearson et al, 2007;Elith et al, 2011;Yousefi et al, 2018b), find new potential habitats for rare and endangered species Abstract: Within its range, the Caspian green lizard, Lacerta strigata, occurs in the Elburz Mountains (northern Iran) at elevations from below sea level to approximately 2700 m a.s.l. To determine the environmental factors affecting the distribution of this lizard, we used an ensemble approach to model the distribution of the Caspian green lizard (Lacerta strigata) in Iran using four algorithms (generalized boosted model, maximum entropy, generalized linear model, random forest).…”