1.a. Tick Collections and Community Science
Large-scale sampling can pose many challenges for researchers and incur substantial personnel costs. By employing a mixed collection strategy across the known geographic range of I. scapularis, our study was able to obtain broad sampling coverage without excessive cost or time input. Obtaining tick samples from research scientists provided consistent collections from a variety of locations and using their collections for this study provides a model for leveraging the efforts of routine tick surveillance programs into fundamental investigative research. Working with community scientists for sample collection in areas without a strong research presence had challenges. For example, not having control over which counties were targeted in the collections; some collection kits being returned with few ticks making it difficult to have a full population represented; and the added responsibility of keeping in contact with volunteers throughout the collection period. However, community scientists allowed us to scale-up the populations sampled significantly from previous I. scapularis population genetics studies and provided an opportunity to increase awareness about the risk of tickborne disease in many communities.
Our dataset is not balanced regarding sex ratios or populations per region. We have more male than female samples, however, completing analyses with a single sex did not produce significantly different results, and keeping both sexes represented allowed more populations to be analyzed. Tick collection efforts are higher in the North, especially the Northeast, due to high Lyme disease incidence and public health surveillance, making samples more readily available. The unevenness in sampling location does not appear to impact results, because all trends hold even with sub-selected populations to make balanced representations of the quadrants (analyses not shown).