IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt


Over half of the World’s salamanders are facing extinction. It is important to understand the impact Humans have on them in all parts of their ranges so we can better understand what they need and how we can prevent further extinctions. I conducted this study to try to determine if the human activity on the official hiking trails in the Arcata Community Forest in Arcata California; as designated by the official map of the Forest; is negatively impacting the salamanders that live in the Forest. I thought there would be an increase in the number of species and the overall number of salamanders as the plots got further away from the hiking trails. I conducted area constrained searches to examine the individual abundance and species diversity of salamanders in the Arcata Community Forest to their distance from the hiking trails. I also examined the correlation between the salamanders weight and snout-vent length to the distance from the trail the salamanders were found at. The salamanders were located and measured using a series of area constrained searches inside 1x1 meter plots, with a distance of at least 20 meters between them. The plots covered an area from 0 to 11 meters away from the trail. The salamanders were bagged, identified to species, then weighed and measured from their snout to their vent. The data was analyzed using Spearman’s Rank Correlation analyses and used t-values to determine the significance of the correlations. The p-values for the Spearman’s Rank Correlations for the species number to the distance from the trail and the number of individual salamanders to the distance from the trail both came back as having significant correlations with higher numbers of species and individuals closer to the trails. This could mean the trails are acting as ecological traps for the salamanders, so the trails and their associated human activities may still be harming the salamanders, despite the salamanders seemingly being drawn to the trails instead of staying away from them like I thought they would. Follow up studies are needed to determine if this is a case of an ecological trap.



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