Insects, arachnids, and other terrestrial arthropods account for 90% of the world’s described animals and play a crucial role in maintaining ecosystem stability. Over the past several decades, insect and arachnid richness and abundance have declined. Drivers of insect declines include habitat loss, pesticide use, climate change, and light pollution, among other stressors. Causes of arachnid declines are less well-understood but generally assumed to be similar. Still, these taxa are often overlooked in legal protections for endangered species. In this thesis I first quantify insect and arachnid biodiversity in the continental United States and Canada and the extent to which species’ conservation status has been evaluated. I examine why state policies for protecting endangered insects and arachnids differ in the United States, then determine the role taxonomic bias, extinction risk, and functional traits play in state and federal insect and arachnid protections. I find the conservation status of most insect and arachnid species in the region is unknown and that this reduces their likelihood of receiving legal protections. I identify the percentage of a state’s GDP that comes from oil and gas extraction and mining as determinants of state policy and public perceptions of wildlife as the driver of how many species a state lists. I also find that taxonomic order influences federal and state legal protections, with odonates, lepidopterans, and hemipterans overrepresented in state lists. Given the role data deficiency plays in impeding insect and arachnid conservation, in Chapter 2 I attempt to address a gap in our understanding of spider conservation by examining how spiders respond to light pollution, a proposed cause of insect declines. I test whether the Pennsylvania grass spider, (Agelenopsis pennsylvanica), preferentially build their webs near artificial light in the absence of other stimuli. I then run a choice-conflict experiment in which spiders must choose between placing their web in an artificially lit area without prey or an unlit area with prey. I find spiders preferentially make their webs in artificially lit areas in the absence and presence of prey. While building webs near artificial light may allow them to catch more insect prey in the short-term, the tendency to prioritize light over prey when placing webs may become disadvantageous as insects evolve reduced flight-to-light behavior, creating an ecological trap for spiders. This thesis highlights the ongoing need to assess how insects and arachnids respond to stressors and the need for greater protection for these taxa.