Freezers full of science
Did you know that Environment and Climate Change Canada has not one, not two, but three time machines? They might not be fancy futuristic gadgets like the ones you see in movies—actually, they’re just freezers…lots and lots of freezers full of sediment and animal and plant tissue—but they’re time machines nonetheless.
These very cool (bad pun intended) time machines—the National Wildlife Specimen Bank, the National Aquatic Biological Specimen Bank, and the National Sediment Specimen Bank—let scientists travel back in time to study things like chemicals in our environment. The samples in ECCC’s specimen banks date back to the 1960s and 1970s, when scientists started squirrelling away extra samples they gathered as part of ongoing work on contaminants in the environment, like the Northern Contaminants Program, the Great Lakes Action Plan, freshwater quality monitoring, various fish and bird monitoring programs, and many more.
There are now more than 576,800 containers of samples in the banks, with new ones being added every year, though older specimens do run out after a while. There are a handful of species that form the backbone of the specimen banks, for example, herring gulls and lake trout. These species tend to be at the top of the food chain (so they show the bioaccumulation of contaminants) and are found across Canada (so we get a broad geographic picture of the status and trends). For herring gulls alone, researchers collect 13 new eggs from each of 15 sites around the Great Lakes area every year—that’s 195 new samples per year—and have been systematically doing this since the mid-1970s.
Why do we need the specimen banks? Well, one of the main reasons is that we tend to study what’s already on our radar. If you think about it, this makes sense: it’s hard to study something when you don’t know it exists. But, for instance, in the case of chemicals in the environment, by the time scientists get an inkling that there might be a problem, the chemical in question has already been around causing trouble for quite some time. The specimen banks let ECCC scientists quickly take stock of where and when the chemical started appearing, in what quantities, the impact it may have already had on the environment, how it has been changing over time, and the risk it poses.
Without the banks, scientists would have to study and monitor for years before they had the information they need to inform policies and regulations. Quicker answers mean quicker action to keep Canadians safe and healthy and to protect our environment. For instance, the specimen banks played a key role in providing the evidence needed—including a 30-year trend line—to restrict the use of a major family of flame retardants in Canada, which were shown to move through the food web, eventually making their way to humans where they can affect the nervous system and hormone levels.
While the focus of the banks is on contaminants, they can tell us about more than that. For example, they can help scientists dig into questions about how the genetic make-up of species is changing, including the emergence of subspecies. The Wildlife Specimen Bank is currently collaborating with the University of Guelph and Queen’s University to study how the DNA of some of the bird species stored in the bank has changed over time to adapt to climate change, industrial development, and other pressures.
The specimen banks can also provide key information about how food webs are changing due to the influence of invasive species and climate change. Using samples from the bank, scientists were able to use chemical fingerprints to show how seabird diet was changing as a result of changes in sea ice (due to climate change). They were also able to use preserved fish tissues and herring gull eggs from the Great Lakes to show how diets and foraging behaviour of these species changed after the invasion of zebra mussels, quagga mussels, and the round goby.
And the specimen banks can even help scientists develop and/or validate new methods. For example, scientists have been using the collection of egg shells to compare egg colour and shell pattern to the level of contaminants inside the egg. This will allow scientists to quickly get a sense of the sort of contaminant levels present just by looking at an egg in the field, which could lead to faster results, better insights, and quicker action.
As new chemicals are put into use in our daily lives and as our ecosystems continue to be altered by the influences of climate change and invasive species, ECCC’s specimen banks will keep playing a vitally important role in helping our scientists understand these new and emerging threats. The quick answers they can provide will continue to lead to timely, evidence-based action to protect the health of Canadians and our environment.