Marine mammals in the North Atlantic have experienced severe depletions due to overexploitation. While some species and populations have now recovered, there are numerous other anthropogenic activities impacting their North Atlantic ecosystem. Studying marine mammals is often associated with logistical challenges, and many species have an elusive nature, resulting in substantial knowledge gaps on the distribution, abundance and diversity of marine mammals in the North Atlantic. Environmental DNA (eDNA) is an emerging tool in biodiversity monitoring and has successfully been demonstrated to complement traditional monitoring methods for a wide range of marine taxonomic groups. The promising potential of seawater eDNA is owe to advances within an array of molecular methods used to extract, detect and/or sequence the genetic material of marine organisms from a single seawater sample.
We present a literature review of eDNA studies of marine mammals and discuss the potential applications and practical challenges of eDNA in marine mammal research, management and conservation.
Environmental DNA has already been introduced to a wide range of applications within marine mammal science, from detection of endangered species to population genetic assessments. Furthermore, eDNA has the power to capture other biologically important species in the marine ecosystem and food web, which could facilitate insight into the spatiotemporal variation of different marine communities in a changing environment. With methodological and technological standardization, eDNA based approaches have a promising potential to be integrated into regular monitoring practices and management strategies.
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The crossover from microscopy to genes in marine diversity: from species to assemblages in marine pelagic copepods
An accurate identification of species and communities is a prerequisite for analysing and recording biodiversity and community shifts. In the context of marine biodiversity conservation and management, this review outlines past, present and forward-looking perspectives on identifying and recording planktonic diversity by illustrating the transition from traditional species identification based on morphological diagnostic characters to full molecular genetic identification of marine assemblages. In this process, the article presents the methodological advancements by discussing progress and critical aspects of the crossover from traditional to novel and future molecular genetic identifications and it outlines the advantages of integrative approaches using the strengths of both morphological and molecular techniques to identify species and assemblages. We demonstrate this process of identifying and recording marine biodiversity on pelagic copepods as model taxon. Copepods are known for their high taxonomic and ecological diversity and comprise a huge variety of behaviours, forms and life histories, making them a highly interesting and well-studied group in terms of biodiversity and ecosystem functioning. Furthermore, their short life cycles and rapid responses to changing environments make them good indicators and core research components for ecosystem health and status in the light of environmental change. This article is part of the theme issue ‘Integrative research perspectives on marine conservation’.
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- Award ID(s):
- 1840868
- NSF-PAR ID:
- 10280246
- Date Published:
- Journal Name:
- Philosophical Transactions of the Royal Society B: Biological Sciences
- Volume:
- 375
- Issue:
- 1814
- ISSN:
- 0962-8436
- Page Range / eLocation ID:
- 20190446
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1098/rstb.2019.0446
