The New Mexico Rare Arthropod Resource

The threats for this species have not been adequately researched and more work is needed on this front. However, climate change is almost certainly the major threat to this subspecies E.a chuskae’s closest relative E.a. cloudcrofti has recently been driven to near extinction a concerning situation as it shares an almost identical habitat to this subspecies in the Sacramento mountains and has a very similar known life history. E.a. cloudcrofti has recently been designated as a federal endangered subspecies due to the sharp declines its experiencing (Ferris and Holland 1980, USFWS 2023). The threats that have driven E.a. cloudrcrofti are also present with E.a. chuskae and almost certainly having a similar effect. Firstly, climate change is driving these narrow mountain endemics and their host plants to higher elevations and at some point as this continues they will eventually have nowhere else to go (Gottfried et al. 2012, USFWS 2023). Having hundreds of miles of inhospitable desert separating these taxa from the next further north sky islands makes them unable to move themselves further north to escape the effects of this climate warming (USFWS 2023). Additionally, major droughts in the southwestern United States have killed off host plants, decreased nectar quality, and available moisture that these species need to survive (Forister et al. 2010, Phillips et al. 2018 ). These droughts are expected to continue to get worse in the American southwest and as such pose a major threat to this taxons long term survival (Cook et al. 2009, Forister et al. 2010, Cook et al. 2015, Williams et al. 2022, Forister et al. 2023). This is especially true as there is some evidence that areas of high moisture such as streams or marshes are extremely important to this subspecies (Bureau of Reclamation 2008). This taxa is also threatened by fire suppression which can erase the meadow habitats that this taxa relies on (USFWS 2004). Extreme temperatures from climate change and the fact that this taxa only has a single known host plant also put this taxa it significant risk for phenological mismatch which has been documented as driving other checkerspot species metapopualtions to extinction (Singer and Parmesan 2010, Patterson et al. 2019). This taxa also only has a single brood a year which makes this taxa much less adaptable to threats and puts at increased risk of extinction (Forister et al. 2023). 

Additionally, another major issue that has had a drastic effect on E.a. cloudcrofti is grazing from horses (USFWS 2023). In the Chuskas free ranging sheep and goats have devastated much of the local vegetation in the area and this taxons host penstemon is likely seeing declines similar to those in the Sacramento mountains due to grazing (USFWS 2023). Holland (1984) also reports ongoing poorly regulated lumber operations in the subspecies habitat which occur over wide areas and use minimal erosion control measures or understory protection (Holland 1984). This could severely impact the quality of habitat available for this taxa and this taxa already exists in such a small range that any loss of habitat especially with climate change driving it to higher elevations could be extremely detrimental. Due to the threat from climate change and drought this species is thought to be experiencing slow continuous declines driving the taxa to extinction however, one very severe drought, fire, or extreme weather event could likely drive this taxa to extinction as a result one location has been determined for this taxa. This is especially likely as Euphydrys anicia and its subspecies also exist in a metapopulation dynamic where patches regularly go extinct and rely on recolonization from sub-populations in neighboring patches (USFWS 2004). This metapopulation dynamic makes checkerspots extremely difficult to conserve and puts them at a significantly increased risk of extinction (Ehrlich and Murphy, 1987, Saccheri et al. 1998). This balance between extinction and recolonization is key in a metapopulation however, with climate change and fire suppression this balance is getting much more difficult to maintain and when populations go extinct like usual they are no longer being recolonized leading to declines in these species (USFWS 2004). This makes the taxa especially vulnerable as it is likely relying on very few reservoir populations to try to recolonize these patches and if fires, fire suppression, or drought eliminates these reservoir populations then the surrounding populations are not viable on their own. Extinction of these subpopulations or threats such as climate change and fire suppresion which reduce habitat for this taxa can also isolate parts of the metapopulation in which case they quickly fall into cycles of inbreeding depression drastically increasing their chances of extinction (Saccheri et al. 1998, Nieminen et al. 2001).