Project Overview

Brown trout were introduced to the Falkland Islands from the UK and Chile in the 40’s and 50’s for recreational fishing, since they have spread form their original sites of introduction, and there has been a marked decline in the presence of the native fish species, zebra trout (Aplochiton zebra and Aplochiton taeniatus) and Falklands minnow (Galaxias maculatus). The aim of this PhD project is to determine the distribution of both brown trout and the native galaxiids, assess the population structure of brown trout and determine the levels of gene flow between brown trout populations and their impacts on native galaxiids. This project also aims to determine how brown trout have spread around the Falkland Islands. Any findings may allow us to protect areas with native fauna that brown trout have not as yet exploited.

Project Objectives

(1) determine the abundance and distribution of invasive brown trout and native galaxiids, zebra trout Aplochiton zebra and Aplochiton taeniatus and the Falklands minnow Galaxias maculatus. (2) assess the level of competition and impacts of brown trout on native galaxiids and (3) estimate the patterns of movement and levels of geneflow between different rivers and populations of brown trout in the Falklands. To address these questions, I am  using state of the art methods including SNP genotyping, stable isotope analysis, acoustic tracking, and environmental DNA (eDNA) analysis.
This project aims to provide resource managers with information to facilitate conservation planning to minimize
impacts of brown trout on native galaxiids.

Highlights 2019-2020
• Completing analysis of an eDNA study to detect the presence of brown trout and both A. zebra and A. taeniatus from DNA present water samples and publishing the results in Environmental DNA.
• Retrieving and downloading data from deployed acoustic receivers. In addition to securing funding and purchasing an additional 30 acoustic tags to be used to monitor movement of brown trout between rivers in the Falklands.

Paper Citation
Minett, J. F., Leaniz, C. G. de, Brickle, P., & Consuegra, S. (2020). A new high- resolution melt curve eDNA assay to monitor the simultaneous presence of invasive brown trout (Salmo trutta) and endangered galaxiids. Environmental DNA, 1-12. http://doi.org/10.1002/end3.151