Center of Expertise in Marine Mammalogy

Scientific Research Report
2015-2017

Table of Contents

• Complete Text
• Introduction
• Using aerial infrared images to count ringed seals on ice
• The use of unmanned aerial vehicles (UAV)
• 2017: A Marine Mammal Odyssey, Eh!
• Mark-recapture analysis from long-term study on Sable Island identifies changes in demographic rates in northwest Atlantic Grey Seals
• OTN – Using grey seals (Halichoerus grypus) as bioprobes to estimate phytoplankton biomass
• Northwest Atlantic International Sightings Survey (NAISS) of Marine Megafauna on the Continental Shelf From Northern Labrador to the Bay of Fundy
• Monitoring Movements of Whelping Seals on Drifting Pack Ice
• Marine Mammal Genomics Research in the Central and Arctic Region
• OTN and predator-prey interactions
• Listening in on the Deep: Passive Acoustic Monitoring of Whales off Nova Scotia
• Sharing Meals Keeps Killer Whale Families Together: Provisioning relatives maintains long-term social bonds and helps pass on shared genes
• New developments in the use of fatty acids to determine marine mammal diets
• More than a mouthful – unlocking bowhead whale foraging and reproductive histories from baleen
• Observing walrus behaviour at haulout sites in quasi real-time
• Moving towards automated counting
• References

Observing walrus behaviour at haulout sites in quasi real-time

Arnaud Mosnier and Mike Hammill

Walrus follow a typical pinniped life history strategy combining marine foraging with hauling out on land or the ice to rest and for reproduction. The effects of climate change are already impacting seasonal ice cover. In the future, walrus are expected to have fewer haulout options as summer pack ice recedes, forcing animals to make greater use of a restricted number of terrestrial sites and limiting availability of foraging areas to those in proximity to these haulout sites.

In Canada, a decline in ice cover may impact walrus, but perhaps not as severely as in the Pacific, where walruses are making extensive use of the offshore pack-ice. One potential benefit is that as summer ice cover declines, animals will make greater use of islands and coastal areas which may be easier to survey to derive abundance estimates. Currently, coast surveys are characterized by considerable uncertainty in the day to day numbers of walruses hauled out at any one time and uncertainty in the proportion of the population hauled out. One approach to improving our understanding of changes in counts of walrus at haulout sites is to increase the number of overflights of key sites during surveys, which is expensive and time consuming.

The deployment of remote cameras at principle haulout sites could provide information on numbers of walruses using a site on a daily basis, information that could be incorporated into surveys. At the same time, cameras could record activity patterns on daily and seasonal haulout use. Data can be stored and downloaded onsite later in the season. However, this approach is cumbersome and would mean data are not available until a year later when the site is revisited. Transmission of remote data via mobile telephone and VHF networks is common but is not possible on walrus haulout sites because they are generally located far from any human installations. The use of satellite communications is becoming more affordable and some companies are developing smaller systems that can take advantage of such technology.

A tower mounted digital camera was installed in early August at an haulout site along the Nottingham Island coast, located in the Hudson Strait, north of the Nunavut Inuit community of Ivujivik. The choice of the site was based on the local knowledge of the hunters and the installation was conducted in collaboration with them. The camera system is powered by a solar panel and a rechargeable battery pack provides electricity to the camera and the satellite modem allowing the transmission of the data. A small weather station installed on another part of the tower also records the wind speed and direction along with the temperature. The camera is programmed to take several pictures per day so as to cover the daily patterns of occupation of the site by walrus. Among those photos three are transmitted through satellite to a website that can be accessed from DFO’s Maurice Lamontagne Institute. This allows us to recover the information collected in quasi real-time (photos are uploaded daily). The photos are also accessible to local hunters allowing them to observe what is happening with walrus as well.

This first installation is a test from various points of view. The plan is to deploy the system on site during one year as a test to see how it will react to the harsh conditions that can occur in this area. This is also a test for the feasibility of the use of satellite transmission in those conditions, including during the winter, when the limited number of daylight hours may limit the solar panel’s abilities to keep the system operational. Depending on the result of this project, similar systems could be deployed at other walrus haulout sites and be used to monitor other species, including for example the monitoring of the use of some estuaries by belugas.