Research

Utilizing empirical, remotely sensed and modelled data, our research is broadly focused on understanding the impacts of environmental variability on large whales and their prey.

To tackle this research, we focus on 1) studying whale behaviour and movement using multi-scale tags; 2) collecting oceanographic data about the biophysical environment; and 3) assessing the impact of disturbance (e.g., new predators, altered feeding conditions, human threats).

Our research takes us to across temperate and Arctic areas. Here’s a look at some of the species we’re studying:

A variety of technologies are employed to study the movement and behaviour of whales, as well as the prey field conditions they encounter. Here are the most commonly used tools in our kit: 

Whale Research

  • These are attached to whales to track their movements over large distances. They provide data on migration patterns, feeding grounds, and coarse-scale behavior over two-dimensional space (horizontal and vertical).

  • Hydrophones are deployed underwater to listen for whale vocalizations. This helps in understanding the communication, social behavior, and distribution patterns of whales.

  • These include high-resolution inertial sensing tags that record data such as depth, temperature, and acceleration. They are also equipped with either an underwater camera and/or a hydrophone to confirm whale behaviour. Tags are attached for hours to two days and provide detailed information about the orientation and movement of whales, shedding light on their behaviour in three-dimensional space. 

  • Satellite imagery and other remote sensing technologies are used to monitor oceanographic conditions, such as sea surface temperature, chlorophyll concentration (indicating phytoplankton abundance), and ocean currents.  Satellite images can also be used to detect whales from space! This data helps in understanding the distribution of prey species and their availability to whales.

  • Genetic techniques are used to study the diet composition of whales by analyzing DNA from skin samples or feces. This helps in understanding how changes in prey availability affect whale feeding ecology.

  • Still imagery and video collected from drones provides a new perspective on whale behaviour and helps inform our sampling in near-real time. We also use imagery to evaluate the body condition of individual whales by making standardized morphometric measurements. Thanks to long-term datasets collected by colleagues at Fisheries and Oceans Canada (e.g.,Drs. Steve Ferguson and Cortney Watt), we can help track population nutritive health over time. 

  • Mathematical models are used to simulate the interactions between whales and their prey in response to environmental changes. These models incorporate data from various sources to predict how whale populations may be impacted by shifts in prey distribution and abundance.

Ocean Conditions

    • Nets with fine mesh sizes are used to collect zooplankton samples from different depths in the water column.

    • These samples are then examined under a microscope to identify and enumerate zooplankton species.

    • Researchers analyze the composition, abundance, and distribution of zooplankton populations to understand their role in marine ecosystems.

    • OPCs are automated instruments that use optical sensors to count and size particles in seawater.

    • They are deployed at discrete depths in the water column to provide real-time data on plankton abundance and size distribution.

    • OPCs are useful for studying variations in plankton populations over time and space, and for assessing the impact of environmental factors on plankton dynamics.

    • This instrument captures images of plankton as it descends through the water column.

    • It provides high-resolution data on the abundance, size, and taxonomic composition of plankton at different depths.

    • The images collected by the profiler allow researchers to study the vertical distribution of plankton and understand their ecological roles in marine ecosystems.

    • These instruments emit sound waves at multiple frequencies and measure the echoes reflected back from organisms in the water column.

    • Multi-frequency echosounders are used to characterize the horizontal and vertical distribution, abundance, and biomass of zooplankton and fish.

    • They provide valuable data for studying predator-prey interactions, migration patterns, and ecosystem dynamics in the ocean.

    • Environmental DNA (eDNA) sampling involves collecting water samples and analyzing them for genetic material shed by organisms present in the environment. 

    • eDNA analysis can identify the genetic signature of multiple trophic species, including zooplankton, fish, and marine mammals.

    • This non-invasive sampling technique provides insights into species diversity, community structure, and ecosystem health in marine environments. We’re fortunate to be working with researchers (Dr. Julie LaRoche) and engineers (Dr. Vincent Siben) from Dartmouth Ocean Technologies and Dalhousie University on this exciting project!

By utilizing these oceanographic sampling techniques, we gather comprehensive data on zooplankton and their interactions with the surrounding environment. This information is essential for understanding the effects of anthropogenic impacts on marine ecosystems.