December 22, 2024 | Evolutionary Fish Ecology

On 19-20 July, our lab temporarily transformed into a genetics laboratory, as Nina Therkildsen and her post-doc Aryn Pierce Wilder visited us from Cornell University (Therkildsen Lab). Their lab also shares the fascination for the Atlantic silverside as a model organism and has set out to eventually assemble the fully annotated genome of this species.

During their visit, they could accompany us for our bi-weekly beach seining in Mumford Cove, where we collected juveniles born this year as well as the last few spawning ripe adults at the end of the season. It was a great summer morning and fun for everyone.

In the lab, Nina and Aryn went on dissecting different types of tissue (muscle, liver, spleen, gills, fins) from a few specimens destined for genetic analyses. In the Rankin lab, we tried a novel procedure on this species, i.e., making haploid embryos by fertilizing strip-spawned eggs with sperm that was UV-radiated before.

Thank you for visiting, Nina and Aryn, and we will see you back in fall, when Nina will give a Friday seminar on 11 November 2016. We’re looking forward to what she will have to report!

Chris and Aryn prepare to take the beach seine to the water
Aryn has clearly fun beach seining
On 19 July 2016, Nina and Hannes pull the first of two seines in Mumford Cove
On 20 July 2016, Aryn prepares samples of silverside tissues for genetic analyses
On 19 July 2016, Nina dissects different tissues from adult silvesides for genetic analyses
A careful squeeze of a silversides belly reveals whether a male or female is in spawning condition
Hannes placing a bucket with water to collect silversides live
Atlantic silversides from Mumford Cover swimming in a bucket
Juvenile and adult silverside captured by beach seine in Mumford Cove on 19 July 2016
Some eggs could be fertilized with sperm that was UV-radiated before in order to make haploid embryos
On 19 July 2016, our lab took Nina and Aryn beach seining (left to right: Chris, Aryn, Wes, Hannes)
On 19 July 2016, Chris and Aryn pull the beach seine ashore, while Wes and Hannes prepare for retrieving the bag

On a balmy July 1st the lab returned to Mumford Cove excited at the prospect of seining without dawning waders for the first time this year! Chris and Rafeed conducted the first seine while Jake remained on the beach and photographed the experience. On the second seine, Hannes accompanied Rafeed while Chris weighed the first sample. As expected the species richness and diversity of the seines were less than that of previous excursions. The abundance of silversides was down, while their sex ratio was skewed towards females. Despite a decline in mature silversides, several juveniles were caught, indicating a budding cohort. Perhaps more young silversides will find their way into the lab’s net in the future. Only time will tell!

Evolutionary Fish Ecology

Month: July 2016

[Collaboration] Nina and Aryn visit from Cornell University

[Lab News] The new silverside generation is here!