“The Exploration of the Pacific”
Marine Mammal Science and Conservation
November 27, 2007 at 2:24 pm · Filed under Science, Conservation
I've been with working with Ari Friedlaender and David Lavigne (see collaborators page) on a project examining sea ice dynamics in the North Atlantic and their effects on breeding pagophilic seals. Previously, we established that the mode of the North Atlantic Oscillation contributes strongly to the amount of sea ice 
off eastern Canada (study available here). This is an important breeding site for harp and hooded seals, and these animals depending on ice as a platform to give birth to and nurse their pups. We've recently expanded this study to look at the other breeding sites for harp seals - the West Ice and the White Sea. While the results are certainly preliminary (and soon to be presented at the CLIOTOP 2007 meeting), at right is a sneak-peek at one of the results. As we found previously, sea ice tends to be in phase with the NAO signal - meaning that when the NAO is positive, there is greater and more persistent sea ice. Interestingly, it appears that the White Sea is actually out of phase with the NAO, exhibiting lower ice concentrations when the NAO is positive. Cool stuff, and more to come.
September 25, 2007 at 7:10 pm · Filed under Science, Conservation
We know that spinner dolphins need to rest during the day, and that they use inshore areas that are also frequented by the dolphin Paparazzi. Pretty much everyone I talk to about spinner dolphins and interactions with humans brings up the idea of dolphin "choice" during encounters. The dolphins approached me or the dolphins came to me. The fundamental core of most of these discussions revolves around the concept that because dolphins "choose" to approach people that enter their resting areas, it's ok and does dolphins no harm (see here for some further background). Basically, the argument relies on the assumption that dolphins make rational decisions during these interactions, weighing the benefits and costs of deviating from their current behavioural state (in this case resting) to play with humans that are moving into their habitat. But is it really appropriate to assume this is all good?
I can think of at least one, good biological imperative that may elicit this type of behavior in dolphins. Clearly these animals require sustained vigilance to avoid predation, which includes investigating potential threats. Perhaps dolphins are not happily making rational decisions about how best to spend their "free" time in these encounters, but instead are acting on instincts telling them that assessing threats is a useful and important thing to do - regardless of what ever else they might be doing, including getting some much needed rest. Better to be tired than dead.
It might be useful to draw an analogy in regards to the choices that dolphins make around humans, just a bit more food for thought when observing and interpreting their behavior. In many places in Canada and in Alaska, humans have established garbage dumps to deal with waste. This is an important function required by human settlements. However, it has the unintended effect of attracting bears to the dumps to take advantage of food waste that is left there. This is often bad news for bears - they eat things they shouldn't, become reliant on the presence of food waste, and this behavior frequently brings them into close (and often harmful) interactions with humans. A fed bear is a dead bear. Clearly these bears choose to frequent the dumps, but I'm sure that no one would argue that it is good for the bears (or humans). In our case with dolphins in resting areas, there are biological reasons that dolphins might break from resting behavior to investigate a well-intentioned human presence in their local environs. They may choose to do this, but it still interrupts their resting behavior and alters the "normal" pattern of the day. I find it difficult to argue that this could be good for dolphins, and in fact it speaks to exactly the opposite.
At what point did we start holding animals to higher standards than humans when it comes to making decisions ? Lots of people I know make decisions that could be considered bad for them (like drinking too much Caol Ila). In most cases human societies have developed social taboos, rules and even laws to encourage people to make better decisions - and that doesn't always work. Considering we don't expect people to make rational and appropriate decisions, why do we implicitly assume that dolphins always will?
Seems like a good idea to develop some rules for humans to help dolphins make better decisions, or at least help them avoid making poor ones.
September 22, 2007 at 10:45 am · Filed under Science, Conservation, Monument
I think that one of the most rewarding things about science is the inherent continuity of the process - where one project's results (whether expected or not) - lead to yet another set of questions and hypotheses and so on…
For example, our recent study of humpbacks wintering in the Northwestern Hawaiian Islands was based on the investigative work by Kristin Rasmussen and her colleagues studying humpbacks in other ocean basins (recently published in Biology Letters). The habitat envelope they described was the real primer for our simple predictive model of humpback wintering habitat in the NWHI published recently in ESR. One thing leads to another.
And it continues. The idea of predicting the distribution and density of marine mammals using environmental correlates is a hot topic right now in marine mammal science. This technique lends itself well to the practical needs of planning and ecological assessment processes, where spatially-explicit information on the potential effects of exposing marine mammals to some risk (e.g. anthropogenic noise or vessel strikes) is required. It's also really useful for setting spatial limits for marine protected areas and defining critical habitat for a species. In our case, it is becoming clear that predicting the core breeding habitats for humpback whales, at basin or global scales, may be a useful and important exercise for conservation purposes. And it might be a relatively easy things to pull off, using existing data that are available for most, if not all, of the worlds oceans.
So we are putting our heads together to tackle this idea. Right now a core group of researchers, including Daniel Palacios, Kristin Rasmussen, Joe Mobely, David Mattila, Ari Friedlaender and myself are embarking on a project aiming to build predictive models of humpback habitat at large scales. This core group of researchers represent a large amount of expertise when it comes to humpbacks, oceanography, statistical modeling of habitat parameters and I'm excited to be taking part in it.
We're still getting going with the project. A draft prospectus has been circulated amongst the researchers and we've set up a website to represent the project and communicate our ideas and initial results. You can check it out here: http://marineresearch.ca/habitat/
September 20, 2007 at 7:22 pm · Filed under Science
I spent a good portion of last week in Seattle attending an agency-wide workshop dedicated to reviewing and revising the methods we use to assess whether or not anthropogenic injuries to marine mammals are likely to lead to their death. If they are, then they are considered a serious injury and are counted against the PBR of the stock.
This is no easy task, especially for our situation in Hawaii, where the interactions occur usually in poor lighting conditions and animals are almost always difficult to identify, let alone trying to assess the extent to which they may be hooked or entangled in gear.
Fortunately, there are a set of criteria we can use to judge these things, and considering the flavour of discussions at the workshop we may be on our way to using a more explicit and transparent assessment process. Several of us at the workshop argued strongly for the application of a risk analysis/decision tree approach, where each component of the assessment is separated out and examined, then the whole thing is reassembled in a framework that illustrates how you get to the endpoint. This approach can incorporate all sorts of "data" for making decisions, and can also include ethical decisions and weighting, as well as input from other stakeholder groups. This type of process allows everyone to see exactly how and why a serious injury is assigned, and helps address the uncertainties that so commonly arise in these assessments.
The other great thing about last week was seeing old friends and getting to catch up with folks. I spent a lot of time with Andy Read, my PhD advisor, and got to hang out with a bunch of people from the east coast that I haven't seen in years. Cool. It was clearly a celebratory event, and one part of it has been immortalized in high art. Below is a somewhat-abstract depiction of a dinner attended by myself, Tim Cole, Jeremy Rusin, Mike Simpkins and Kristy Long. Who is who? Well, Kristy is pretty easy to pick out, Tim was wearing a striped shirt and Mike has glasses…good luck!
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off eastern Canada (study available here). This is an important breeding site for harp and hooded seals, and these animals depending on ice as a platform to give birth to and nurse their pups. We've recently expanded this study to look at the other breeding sites for harp seals - the West Ice and the White Sea. While the results are certainly preliminary (and soon to be presented at the CLIOTOP 2007 meeting), at right is a sneak-peek at one of the results. As we found previously, sea ice tends to be in phase with the NAO signal - meaning that when the NAO is positive, there is greater and more persistent sea ice. Interestingly, it appears that the White Sea is actually out of phase with the NAO, exhibiting lower ice concentrations when the NAO is positive. Cool stuff, and more to come.
