Allometric Regression of Snake Body Length from Head Image Measurements

ABSTRACT As in many fields of wildlife research and management, camera devices photogrammetry have become an integral part the toolkit for exploring otherwise‐unseen aspects biology, behavior, control invasive brown treesnake ( Boiga irregularis ) on Guam. Because treesnakes are cryptic nocturnal, nearly all their ecology influenced by snake size, methods needed to estimate size from images captured infrared cameras. Unfortunately, it is difficult capture entire snake's length at a controlled distance simple setup. Here, I describe allometric relationships between body potential predictors: head measurements, sex, condition. Head (HL) was most important predictor length, alone accounting 95.9% variation snout‐vent (SVL). We provide regression equations predicting example how extract measurements images, convenient lookup table SVL 80% prediction intervals HL alone. Coupled with setup that controls subject includes standards image, we can include only when photographed above. These been developed enable ongoing assessments predation risk following landscape‐scale suppression efforts could reintroduction extirpated native wildlife. Published 2021. This article U.S. Government work public domain USA. Wildlife Society Bulletin published Wiley Periodicals LLC behalf The Society.