Data from: Molecular detection of invertebrate prey in vertebrate diets: trophic ecology of Caribbean island lizards

Understanding community assembly and population dynamics frequently
requires detailed knowledge of food web structure. For many consumers,
obtaining precise information about diet composition has traditionally
required sacrificing animals or other highly invasive procedures,
generating tension between maintaining intact study populations and
knowing what they eat. We developed 16S mitochondrial DNA sequencing
methods to identify arthropods in the diets of generalist vertebrate
predators without requiring a blocking primer. We demonstrate the utility
of these methods for a common Caribbean lizard that has been intensively
studied in the context of small island food webs: Anolis sagrei (a
semi-arboreal ‘trunk-ground’ anole ecomorph). Novel PCR primers were
identified in silico and tested in vitro. Illumina sequencing successfully
characterized the arthropod component of 168 faecal DNA samples collected
during three field trips spanning 12 months, revealing 217 molecular
operational taxonomic units (mOTUs) from at least nine arthropod orders
(including Araneae, Blattodea, Coleoptera, Hemiptera, Hymenoptera,
Isoptera, Lepidoptera and Orthoptera). Three mOTUs (one beetle, one
cockroach and one ant) were particularly frequent, occurring in ≥50% of
samples, but the majority of mOTUs were infrequent (180, or 83%, occurred
in ≤5% of samples). Species accumulation curves showed that dietary
richness and composition were similar between size-dimorphic sexes;
however, female lizards had greater per-sample dietary richness than
males. Overall diet composition (but not richness) was significantly
different across seasons, and we found more pronounced interindividual
variation in December than in May. These methods will be generally useful
in characterizing the diets of diverse insectivorous vertebrates.