Camera Trap Project Update

María checking on Camera 1.

Since their installation in May, two automatic trail cameras have been photographing two skerries off the west coast of Vatnses. The cameras turn themselves each morning at day break, they then take one photo every 10 minutes, then they shut themselves off when darkness comes after sunset. Also, they are triggered by motion (a feature we cannot shut off) so we get extra photos every time a bird flies close enough to the sensor. Each month, researchers go out to check on the cameras and to switch out batteries and memory cards. The photos are then downloaded to a hard drive and we are combing through the ever-growing collection of photographs to record when seals were hauled out on the rocks and how many there were.

A group of harbor seals hauled out on Skerry 2.

The data collected during this project will be useful in more ways than one. First, it’s a pilot study on the presence and behavior of seals at a location that is being considered for development of a new seal watching site. An important part of the feasibility of this site for seal watching is seal activity. So far, it looks like there are seals hauled out there every time the tide is low enough for the skerries to be exposed. We have been seeing female seals with pups as well as individual seals and adults with no pups. Once all photographs from this year are reviewed, the data will be analyzed to look for trends in behavior. We can investigate changes in the number of seals hauling out at the location from May through December. We can also use these series of photos to estimate how long individual seals on the rocks and possibly to gain insight into what factors influence the patterns we see in their behavior.

Sometimes there is not a breath of movement in the air. Here, some pups born earlier in the summer lie, undisturbed on Skerry 2.

This is being considered a pilot study, which means that we don’t yet know the full detailed results we will get from this. Probably, this project will inspire new questions for further investigation using more precise methods to collect more in-depth data.

Hauled out seals appear to be relaxed at this site even when the weather is not what we would consider perfect. In fact, seals can overheat if the weather is too warm, as they are adapted to the cold water environment.

The Camera Trap Project

The first images from one of our trail cameras shows two skerries and some seals with pups in the center of the bottom of the frame.

A new project is underway. Researchers are collaborating with museum staff in a project to assess the viability of a new site to develop for seal watching and outdoor recreation on Vatnsnes. In order to do this, we have set up two camera traps that record photographs at a set interval of time all day. Researchers then stop in to collect memory cards once each week while they are out counting seals at known haul-outs.

Seals prefer hauling out on skerries that are separated from land by a channel of water. Many of these skerries are more than 100 m from land. In order to set up automatic cameras to photograph seals up close would mean attaching the cameras directly to the skerry. This may be done at some point in the future if funding is acquired. In that case, we would be setting up cameras on those skerries that rise far enough out of the water to remain exposed at high tide. That does not fall within the scope of this pilot project, but is certainly something we are interested in. The cameras we have set up are easily accessible from land with minimal disturance of the seals in the area. If we get the chance to put cameras on serries, we will expect to leave them there for a much longer period between maintenance trips, so as to avoid disturbing the seals.

Installation of one of the trail cameras at the top of the cliff overlooking the skerries we want to monitor

The trail cameras that we currently own needed to be placed at some distance from where the seals haul out. At the location we have chosen, there are two skerries close together and the landowner has told us that a large group of seals congregates here with some regularity. So, we set up two cameras to cover the entirety of the two skerries. These cameras will be in place for some months. All seals observed will be recorded and that data will contribute to the assessment of this location as a possible new seal watching site.

The trail camera is at the top of the cliff on the right hand side of the frame.

Photographs from this project will soon be on display at the Seal Center Museum in Hvammstangi. Looking carefully at images such as these that are taken from some distance is a good way to train your eye to recognize seals even before you can see them clearly. Seals are often easily visible from Iceland’s coastal roads, if you know what to look for. While there are some designated seal watching areas on Vatnsnes and in a few other places in Iceland, a vigilant passenger in the car is likely to spot seals in unmarked spots. Photographs such as the one above can help you to find seals here and elsewhere.

As with many of the projects conducted here, funding for this project comes from outside the Seal Center. Specifically, we appreciate the funding we have received from the National Marine Aquarium for this project.

Estimated population size of the Icelandic harbour seal

In the summer of 2016, an aerial census of the harbour seals along the entire coast of Iceland was conducted. Such aerial censuses are important in monitoring the population size of seals. The first aerial census occurred in 1980 and in that year, the harbour seal population was estimated at about 33.000 animals. The 2016 census provided an estimate of 7.700 animals, which is considerably smaller than the 11.000 – 12.000 harbour seals estimated to inhabit Icelandic waters in the previous aerial census in 2011.

In 2014, harbour seals were counted at the largest haul-outs (places where seals congregate on shore) in Iceland and there was strong indication that the population had decreased and the results of the census last summer show this to be the case. Since 2011, the Icelandic harbour seal population has decreased by about 30%. The current population is estimated to be close to 80% smaller than it was when first investigated in 1980. According to official policy, the Icelandic harbour seal population should not fall below 12.000 animals and if it does, the government must take appropriate measures. The population is currently estimated at just under 40% of the desirable number.

The greatest decrease occurred between 1980 and 1990, when seals were directly targeted at a much higher rate than they are now. Seals are still hunted and while this may account for some of the decrease seen, seals killed as bycatch in fisheries is another factor. Other factors, such as marine warming and variations in the availability of the seals’ prey, can cause some decrease as well. Although the drop in population is considerable, it is important to have in mind that natural variations occur in wild populations and more research is needed before the major causes of the decrease in the Icelandic harbour seal population can be explained.

For the full text of the study, click here.