Recent regional reports and trends in biomonitoring suggest that insects are experiencing a multicontinental crisis that is apparent as reductions in abundance, diversity, and biomass. Given the centrality of insects to terrestrial ecosystems and the food chain that supports humans, the importance of addressing these declines cannot be overstated. The scientific community has understandably been focused on establishing the breadth and depth of the phenomenon and on documenting factors causing insect declines. In parallel with ongoing research, it is now time for the development of a policy consensus that will allow for a swift societal response. We point out that this response need not wait for full resolution of the many physiological, behavioral, and demographic aspects of declining insect populations. To these ends, we suggest primary policy goals summarized at scales from nations to farms to homes.

DNA analysis of predator faeces using high-throughput amplicon sequencing (HTS) enhances our understanding of predator-prey interactions. However, conclusions drawn from this technique are constrained by biases that occur in multiple steps of the HTS workflow. To better characterize insectivorous animal diets, we used DNA from a diverse set of arthropods to assess PCR biases of commonly used and novel primer pairs for the mitochondrial gene, cytochrome oxidase C subunit 1 (COI). We compared diversity recovered from HTS of bat guano samples using a commonly used primer pair "ZBJ" to results using the novel primer pair "ANML." To parameterize our bioinformatics pipeline, we created an arthropod mock community consisting of single-copy (cloned) COI sequences. To examine biases associated with both PCR and HTS, mock community members were combined in equimolar amounts both pre-and post-PCR. We validated our system using guano from bats fed known diets and using composite samples of morphologically identified insects collected in pitfall traps. In PCR tests, the ANML primer pair amplified 58 of 59 arthropod taxa (98%), whereas ZBJ amplified 24-40 of 59 taxa (41%-68%). Furthermore, in an HTS comparison of field-collected samples, the ANML primers detected nearly fourfold more arthropod taxa than the ZBJ primers. The additional arthropods detected include medically and economically relevant insect groups such as mosquitoes. Results revealed biases at both the PCR and sequencing levels, demonstrating the pitfalls associated with using HTS read numbers as proxies for abundance. The use of an arthropod mock community allowed for improved bioinformatics pipeline parameterization. K E Y W O R D SAMPtk, arthropod mock community, bat guano, dietary analysis, insectivore, next-generation sequencing *Indicates shared first authorship based on equal contributions.

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Western monarch butterflies dropped by ∼97% of their average historic abundance between the 1980s and mid-2010s. In winter 2018-2019, the population plummeted even farther, to fewer than 30,000 monarchs, which represents a single year drop of 86% and a drop of >99% since the 1980s. The population may now be hovering at its quasi-extinction threshold. In this Perspectives piece, we: (1) Place the current status in context, (2) Highlight the most likely window during the annual life cycle when the population declined, (3) Review probable causes of long-term declines, and (4) Recommend steps that the public, policy makers, and land managers can take to recover western monarchs. The available studies reinforce the hypotheses that overwintering habitat loss and loss of central California breeding habitat, as well as pesticide use, are likely important contributors to the western monarch's long-term decline. The most limiting part of the migratory cycle appears to be concentrated during the overwintering stage and/or in early spring. If western monarchs are in fact entering an extinction vortex, they need extraordinary efforts-focused on the most vulnerable periods of the annual cycle-to save the migration. Critical short-term conservation priorities are to (1) Protect, manage and restore overwintering habitat, (2) Protect monarchs and their habitat from pesticides, (3) Restore breeding and migratory habitat in California, (4) Protect, manage, and restore summer breeding and fall migration monarch habitat throughout the western monarch's range, and (5) Fill research gaps to inform western monarch recovery strategies.