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iDNA from terrestrial haematophagous leeches as a wildlife surveying and monitoring tool - prospects, pitfalls and avenues to be developed.

Schnell IB, Sollmann R, Calvignac-Spencer S, Siddall ME, Yu DW, Wilting A, Gilbert MT - Front. Zool. (2015)

Bottom Line: Subsequently, we briefly address how the analytical challenges associated with leeches may apply to other sources of iDNA.Our review highlights that despite the considerable potential of leech (and indeed any) iDNA as a new survey tool, further pilot studies are needed to assess how analytical methods can overcome or not the potential biases and assumption violations of the new field of iDNA.Specifically we argue that studies to compare iDNA sampling with standard survey methods such as camera trapping, and those to improve our knowledge on leech (and other invertebrate parasite) physiology, taxonomy, and ecology will be of immense future value.

View Article: PubMed Central - PubMed

Affiliation: Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark ; Center for Zoo and Wild Animal Health, Copenhagen Zoo, Frederiksberg, Denmark.

ABSTRACT
Invertebrate-derived DNA (iDNA) from terrestrial haematophagous leeches has recently been proposed as a powerful non-invasive tool with which to detect vertebrate species and thus to survey their populations. However, to date little attention has been given to whether and how this, or indeed any other iDNA-derived data, can be combined with state-of-the-art analytical tools to estimate wildlife abundances, population dynamics and distributions. In this review, we discuss the challenges that face the application of existing analytical methods such as site-occupancy and spatial capture-recapture (SCR) models to terrestrial leech iDNA, in particular, possible violations of key assumptions arising from factors intrinsic to invertebrate parasite biology. Specifically, we review the advantages and disadvantages of terrestrial leeches as a source of iDNA and summarize the utility of leeches for presence, occupancy, and spatial capture-recapture models. The main source of uncertainty that attends species detections derived from leech gut contents is attributable to uncertainty about the spatio-temporal sampling frame, since leeches retain host-blood for months and can move after feeding. Subsequently, we briefly address how the analytical challenges associated with leeches may apply to other sources of iDNA. Our review highlights that despite the considerable potential of leech (and indeed any) iDNA as a new survey tool, further pilot studies are needed to assess how analytical methods can overcome or not the potential biases and assumption violations of the new field of iDNA. Specifically we argue that studies to compare iDNA sampling with standard survey methods such as camera trapping, and those to improve our knowledge on leech (and other invertebrate parasite) physiology, taxonomy, and ecology will be of immense future value.

No MeSH data available.


Related in: MedlinePlus

Mitochondrial tDNA-based phylogenetic tree including sequences from five leeches reported in [18]. These leeches were collected at a single location in the Annamite Mountains, Vietnam and apparently belong to at least 3 distinct genetic clades
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Fig2: Mitochondrial tDNA-based phylogenetic tree including sequences from five leeches reported in [18]. These leeches were collected at a single location in the Annamite Mountains, Vietnam and apparently belong to at least 3 distinct genetic clades

Mentions: Terrestrial haematophagous leeches have been shown to feed on a wide range of vertebrate species, including birds, amphibians, reptiles and mammals [23, 33]. Although a degree of host-specificity has been recorded for some terrestrial leech species – for example, the species Tritetrabdella taiwana seems to feed primarily on amphibians [34] – it is still not fully understood whether this is a true host preference, or simply an outcome of what animals are present in the same (micro-) habitats as the leeches. Behavioural studies have demonstrated that while coexisting Bornean brown (Haemadipsa sumatrana) and tiger leeches (Haemadipsa picta) both feed on mammals (with no apparent preferences shown within mammals), brown leeches live on the ground, and tiger leeches usually sit on leaves of small trees and bushes [34, 35]. Consequently, tiger leeches are less likely than brown leeches to feed on small, fossorial terrestrial mammals. Thus, even if terrestrial haematophagous leeches are opportunistic feeders, any given species likely will not feed on all vertebrates in an area evenly, and the general lack of knowledge about leech taxonomy (Table 1 and Fig. 2), phylogeography, and behaviour makes it challenging to account for interspecific ecological differences among leeches in both collection and subsequent data analysis.Table 1


iDNA from terrestrial haematophagous leeches as a wildlife surveying and monitoring tool - prospects, pitfalls and avenues to be developed.

Schnell IB, Sollmann R, Calvignac-Spencer S, Siddall ME, Yu DW, Wilting A, Gilbert MT - Front. Zool. (2015)

Mitochondrial tDNA-based phylogenetic tree including sequences from five leeches reported in [18]. These leeches were collected at a single location in the Annamite Mountains, Vietnam and apparently belong to at least 3 distinct genetic clades
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4589908&req=5

Fig2: Mitochondrial tDNA-based phylogenetic tree including sequences from five leeches reported in [18]. These leeches were collected at a single location in the Annamite Mountains, Vietnam and apparently belong to at least 3 distinct genetic clades
Mentions: Terrestrial haematophagous leeches have been shown to feed on a wide range of vertebrate species, including birds, amphibians, reptiles and mammals [23, 33]. Although a degree of host-specificity has been recorded for some terrestrial leech species – for example, the species Tritetrabdella taiwana seems to feed primarily on amphibians [34] – it is still not fully understood whether this is a true host preference, or simply an outcome of what animals are present in the same (micro-) habitats as the leeches. Behavioural studies have demonstrated that while coexisting Bornean brown (Haemadipsa sumatrana) and tiger leeches (Haemadipsa picta) both feed on mammals (with no apparent preferences shown within mammals), brown leeches live on the ground, and tiger leeches usually sit on leaves of small trees and bushes [34, 35]. Consequently, tiger leeches are less likely than brown leeches to feed on small, fossorial terrestrial mammals. Thus, even if terrestrial haematophagous leeches are opportunistic feeders, any given species likely will not feed on all vertebrates in an area evenly, and the general lack of knowledge about leech taxonomy (Table 1 and Fig. 2), phylogeography, and behaviour makes it challenging to account for interspecific ecological differences among leeches in both collection and subsequent data analysis.Table 1

Bottom Line: Subsequently, we briefly address how the analytical challenges associated with leeches may apply to other sources of iDNA.Our review highlights that despite the considerable potential of leech (and indeed any) iDNA as a new survey tool, further pilot studies are needed to assess how analytical methods can overcome or not the potential biases and assumption violations of the new field of iDNA.Specifically we argue that studies to compare iDNA sampling with standard survey methods such as camera trapping, and those to improve our knowledge on leech (and other invertebrate parasite) physiology, taxonomy, and ecology will be of immense future value.

View Article: PubMed Central - PubMed

Affiliation: Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark ; Center for Zoo and Wild Animal Health, Copenhagen Zoo, Frederiksberg, Denmark.

ABSTRACT
Invertebrate-derived DNA (iDNA) from terrestrial haematophagous leeches has recently been proposed as a powerful non-invasive tool with which to detect vertebrate species and thus to survey their populations. However, to date little attention has been given to whether and how this, or indeed any other iDNA-derived data, can be combined with state-of-the-art analytical tools to estimate wildlife abundances, population dynamics and distributions. In this review, we discuss the challenges that face the application of existing analytical methods such as site-occupancy and spatial capture-recapture (SCR) models to terrestrial leech iDNA, in particular, possible violations of key assumptions arising from factors intrinsic to invertebrate parasite biology. Specifically, we review the advantages and disadvantages of terrestrial leeches as a source of iDNA and summarize the utility of leeches for presence, occupancy, and spatial capture-recapture models. The main source of uncertainty that attends species detections derived from leech gut contents is attributable to uncertainty about the spatio-temporal sampling frame, since leeches retain host-blood for months and can move after feeding. Subsequently, we briefly address how the analytical challenges associated with leeches may apply to other sources of iDNA. Our review highlights that despite the considerable potential of leech (and indeed any) iDNA as a new survey tool, further pilot studies are needed to assess how analytical methods can overcome or not the potential biases and assumption violations of the new field of iDNA. Specifically we argue that studies to compare iDNA sampling with standard survey methods such as camera trapping, and those to improve our knowledge on leech (and other invertebrate parasite) physiology, taxonomy, and ecology will be of immense future value.

No MeSH data available.


Related in: MedlinePlus