Sammanfattning

The hound needlefish Tylosurus crocodilus (Belonidae) is a highly demanded fish in the local markets of Tanzania, but the growing coastal population threatens its sustainability. As belonids are highly migratory fishes utilising various parts of the seascape, increased fishing pressure may disrupt connectivity patterns on different spatiotemporal scales and disaggregate populations. Using the COI gene, this study assessed the genetic population structure, connectivity patterns, and historical demography of T. crocodilus collected in seven sites spread along Tanzanian coastal waters. Results showed fourteen haplotypes with low overall nucleotide and haplotype diversity. Pairwise F-ST comparisons revealed no significant differences among the sampled sites, except for the northernmost site (Tanga) and an island in the south (Songosongo). Analysis of molecular variance (AMOVA) revealed a non-significant genetic structure among populations (F-ST = 0.01782), suggesting the fishery across Tanzanian waters exploits the same population. Moreover, there was no correlative relationship between genetic and pairwise geographic distances, rejecting the isolation by distance hypothesis. However, neutrality tests and mismatch distribution analysis revealed that recent demographic expansion might exist. Empirical evidence of panmixia suggests high genetic connectivity. In combination with low genetic diversity, management should be directed to actions that prevent genetic diversity loss and the effect of genetic drift on populations.

Nyckelord

Hound needlefish; population structure; genetic diversity; haplotype diversity; genetic connectivity; >

Publicerad i

Marine Biology Research
2023, Volym: 19, nummer: 4-5, sidor: 261-270
Utgivare: TAYLOR AND FRANCIS AS

SLU författare

• Sköld, Mattias

  • Institutionen för akvatiska resurser (SLU Aqua), Sveriges lantbruksuniversitet
    

Globala målen

SDG14 Bevara och nyttja haven och de marina resurserna på ett hållbart sätt för en hållbar utveckling


UKÄ forskningsämne

Fisk- och akvakulturforskning


Publikationens identifierare

DOI: https://doi.org/10.1080/17451000.2023.2224026

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/123404