Written by Belén García Ovide, PhD Candidate at the University of Iceland (2023)
During the first eDNA sampling season in 2023, best practices for eDNA data collection were tested from July to October in Skjálfandi Bay.
The aim was to collect 18 water samples plus two controls. The data collection was successful and completed on the 23rd of October.
During the field season, I assessed the best strategy that would fit within the existing framework of North Sailing’s whale watching activities and the requirements of the eDNA sampling. Further, to investigate the feasibility of the citizen science approach during eDNA sampling, surveys were disseminated to the public onboard the boats when eDNA sampling took place.
To achieve an optimized sampling strategy for the second field season in 2024, we started testing three different filters suggested by eWHALE (Smith-Root, Sylphium and Sterivex). Smith-Root showed the fastest filtering rate (20 minutes /10 L water) followed by the Sylphium filter (30 minutes / 10 L water).
Water samples were taken twice a week from regular whale watching tours (3h) and dedicated citizen science tours “Whale Sails and Science” (3,5h). At the end of the season, we concluded that both types of tours are adequate to incorporate this research onboard, as long as there are at least two people solely dedicated to collecting the water samples and performing the filtering onboard.
Regarding the citizen science surveys, a total of 81 surveys (before) and 50 surveys (after) introducing the eDNA topic, were filled out during the tours, being so far the highest rate of participation in the eWHALE project this year. This data may be used later for a common publication with the other PhD students at eWHALE.
Who was involved in fieldwork?
The data collection required at least two people. I was mainly the one collecting and filtering water with the assistance of Taime, a team member from the Ocean Missions NGO. Two interns from the University of Iceland Research Center and three North Sailing whale watching guides also took part in the field work when I was not available. I also ensured that the communication between the crew onboard and the people in charge of the sampling was clear and flowed easily and that the captains had enough information to help us take the water samples. In most cases, the reception and communication were very good, and the sampling operation was successful.
When did you go sampling?
Data collection started 5th of July and was performed up to two times a week depending on weather conditions until we reached a total of 18 samples and two controls (on the 23rd of October). All the samples were collected in Skjálfandi Bay (see map).
Which species were you targeting and why?
We were targeting mainly humpback whales as they are the main focus in the eWHALE project. They are the most sighted whale species in the bay and it is relatively easy to approach. The University of Iceland has been studying these whales through photo Identification for more than a decade. Therefore, it is relevant to assess the feasibility to incorporate the DNA approach to the ongoing efforts on humpback whale research in the region. Yet we were willing to try eDNA sampling in other species (eg, minke whales, blue whales) if the opportunity arose.
Were you working with citizen scientists? If so, were they interested in eWHALE?
Passengers were informed about the sampling during the tour; however, they didn’t participate directly in the sampling in order to avoid contamination of the samples. Generally, they were interested and asking questions!
An advantage of the Whale Sails and Science tour, which is organized in cooperation with the Ocean Missions non-profit organization, is the reduced number of passengers (maximum 20). The smaller passenger group facilitates the sampling, enhances the interaction within guests and increases the awareness, whilst it considerably reduces the risks of contamination of the samples. Generally, more people were interested in this kind of tour.
The high participation on the DNA surveys demonstrate that people were generally interested in the research and willing to participate. However, the weather was often cold and harsh, demotivating people to focus much on something.
Which other species did you see?
Frequently sighted species were minke whales, white beaked dolphins, bule whales (mainly in late May – beginning of June) and occasionally killer whales, Northern bottlenoses and fin whales. We realized that getting a sample directly from the fluke print of these species can be quite challenging in this area. Obviously, we saw plenty of seabird’s species, including hundreds of puffins that come to breed every summer in our beautiful Puffin Island.
What was the best part of fieldwork?
Besides the many unforgettable encounters with the whales, I think the good atmosphere onboard and the coordination between the crew and the people in charge of the sampling was the best part for me to see. There was a constant feeling of teamwork and for every fluke print we got, everyone was excited and celebrated, including the passengers onboard! so I think it was definitely bringing added value to the tours, specially in the regular whale watching tours.
What was the most interesting thing that happened in the field?
Several very interesting things happened while we were collecting samples in our bay, such as the day we were able to sample a stream that came from Greenland with glacier water. But the one we remember with the most enthusiasm was a day with calm and flat seas, without wind and with a huge sun, when while we were filtering calmly in the stern and all the passengers were in the bow, we suddenly heard two energetic and powerful blows right next to us. Two northern bottlenose beaked whales had appeared! These animals are not at all common in Skjálfandi, but every year they spend a few days in August with us. Being able to enjoy them like this was quite a gift.