Comparing iDNA from mosquitoes and flies to survey mammals in a semi‐controlled Neotropical area

Abstract

Ingested‐derived DNA (iDNA) from insects represents a powerful tool for assessing vertebrate diversity because insects are easy to sample, have a diverse diet and are widely distributed. Because of these advantages, the use of iDNA for detecting mammals has gained increasing attention. Here we aimed to compare the effectiveness of mosquitoes and flies to detect mammals with a small sampling effort in a semi‐controlled area, a zoo that houses native and non‐native species. We compared mosquitoes and flies regarding the number of mammal species detected, the amount of mammal sequence reads recovered, and the flight distance range for detecting mammals. We also verified if the combination of two mini‐barcodes (12SrRNA and 16SrRNA) would perform better than either mini‐barcode alone to inform local mammal biodiversity from iDNA. To capture mosquitoes and flies, we distributed insect traps in eight sampling points during 5 days. We identified 43 Operational Taxonomic Units from 10 orders, from the iDNA of 17 mosquitoes and 46 flies. There was no difference in the number of species recovered per individual insect between mosquitoes and flies, but the number of flies captured was higher, resulting in more mammal species recovered by flies. Eight species were recorded exclusively by mosquitoes and 20 by flies, suggesting that using both samplers would allow a more comprehensive screening of the biodiversity. The maximum distance recorded was 337 m for flies and 289 m for mosquitoes, but the average range distance did not differ between insect groups. Our assay proved to be efficient for mammal detection, considering the high number of species detected with a reduced sampling effort.

Testing and optimizing metabarcoding of iDNA from dung beetles to sample mammals in the hyperdiverse Neotropics

“…In addition, while the 16SrRNA mini-barcode was more effective for mammal species detection, the total species number increased by using the 12SrRNA barcode (Figure 2). Similar trends were also reported when both primer pairs were used to amplify iDNA obtained from mosquitoes and carrion flies (Saranholi et al, 2023),…”

“…Although Saranholi et al (2023) reported higher mean values in mosquitoes (3.6 ± 4.3 OTUs) and carrion flies (saprophagous flies:…”

“…For each specimen, mitochondrial 12SrRNA and 16SrRNA rRNA genes were amplified using the primers 12SV5F and 12SV5R (Riaz et al, 2011) and 16Smam1 and 16Smam2 (Taylor, 1996) to produce amplicons of approximately 130-140 bp. These mini-barcodes are commonly used in iDNA studies for mammal community detection (Lynggaard et al, 2019;Massey et al, 2022;Rodgers et al, 2017;Saranholi et al, 2023),…”

“…Mammal biodiversity monitoring can especially benefit from iDNA approaches as many species have elusive behaviour and can be rare or present in low population densities, especially within degraded habitats (Ripple et al., 2014). Several groups of invertebrates have been proven to be efficient for sampling vertebrate DNA, such as carrion flies (Calvignac‐Spencer, Leendertz, et al., 2013; Calvignac‐Spencer, Merkel, et al., 2013; Massey et al., 2022; Rodgers et al., 2017), mosquitoes (Massey et al., 2022; Saranholi et al., 2023), leeches (Fahmy et al., 2019), and dung beetles (Drinkwater et al., 2021; Gillett et al., 2016; Gómez & Kolokotronis, 2017; Nimalrathna et al., 2023).…”

Mosquito bloodmeals can be used to determine vertebrate diversity, host preference, and pathogen exposure in humans and wildlife

“…The diversity of bloodmeal origins captured across a number of mosquito species, con rms that mosquitoes are a powerful, emerging tool for characterising vertebrate diversity. The technique has potential application to a range of ecological and conservation issues, such as monitoring rare or endangered species 44 , and measuring biodiversity 45,46 . It can also be used to understand host feeding patterns, which is a crucial component for assessing the risk of pathogen transmission pathways and human spillover.…”