Thank you.
My name is Anthony Ricciardi. I'm a professor of biology at McGill University. I've studied invasive species for 20 years. My research examines the impacts of invasions in aquatic environments.
There are a few important points I'd like to bring to your attention.
The first point is that there is indisputable evidence that invasions are increasing in frequency worldwide, particularly in large aquatic systems like the Great Lakes. The invasion history of the Great Lakes spans two centuries and shows an increasing number of non-indigenous species being discovered over time.
Since the opening of the St. Lawrence Seaway in 1959, one new invader has been discovered every seven months, on average. This rate is higher than those reported for any other freshwater system for which we have long-term data.
There are at least 187 non-indigenous species that have become established in the Great Lakes since the late 19th century. These include plants, fish, invertebrates, and various kinds of microbes, including pathogens.
One hundred and eighty-seven species is a conservative number because there had to have been invasions that went unnoticed. Furthermore, there are at least 20 additional species in the Great Lakes whose origins are uncertain. We don't know if they're native or non-indigenous.
So we have very likely underestimated the degree to which the system has been invaded, but I can say that it is very likely the most highly invaded freshwater system on the planet.
Another interesting observation is that, as far as we know, every one of those 187 species is still present in the Great Lakes. To my knowledge, not a single non-indigenous species ever established in the Great Lakes has gone extinct or has been eradicated. So what we're seeing in the system is an increasing accumulation of invaders and their impacts over time.
I also want to emphasize that the impacts of the vast majority of these invaders have not been studied. Consequently, we have a poor understanding of how most of them have affected fisheries or water quality. Without this information, we cannot conclude with any certainty that most of these invasions have been benign.
We do know that at least some of these species have had strong impacts on fish communities. In fact, nearly one out of every five invaders that have been discovered over the past 50 years has had significant negative effects on native species populations in the Great Lakes. These include several parasites and disease pathogens that have been found just within the past two decades, such as—you may have heard of some of these—the largemouth bass virus, muskie pox, and VHS, or viral hemorrhagic septicemia. VHS has caused local mass mortalities in fish populations throughout the Great Lakes—except for perhaps Lake Superior—at various times since 2003, when the virus was first detected.
It's not clear whether this recent increase in the discovery of diseases is the result of scientists being better able to detect these organisms, or whether it is a real trend that reflects some increasing vulnerability in the Great Lakes to disease outbreaks.
Several vectors are responsible for delivering non-indigenous species to the Great Lakes. The most important one historically has been ballast water release from overseas shipping. The discharge of ballast water is assumed to be responsible for 60% of the invaders discovered since 1959. These include some of the most disruptive species ever introduced to Canada, such as the spiny water flea, the zebra mussel, the quagga mussel, the round goby, and several others.
In 2006 Canada took an important step in controlling this vector by requiring all ballast water entering the Great Lakes to be at a salinity of 30 parts per thousand—in other words, near the concentration of sea water. This was adopted as a harmonized regulation by the St. Lawrence Seaway Authority—that is, by both countries—in 2008.
Over the past five years since the regulation went into effect, there have been no reported invasions attributable to overseas shipping. I think it is still too early to conclude that the ballast water problem has been solved, because some invasive species can remain hidden for several years before being discovered. However, I believe that the risk of invasion has been greatly reduced, and many of my colleagues share this opinion.
If the risk of ballast water has not been sufficiently reduced, then the Great Lakes remain vulnerable to several immediate invasion threats. There are several potentially harmful species that are currently invading Europe, and they have become abundant at ports from which the Great Lakes receive shipping traffic. One of these is an invertebrate predator known as the killer shrimp. You may have heard of it. It has received a lot of media attention overseas. I've done a risk assessment to identify and rank these species, so I am pretty familiar with what the risks are of the ones that are currently invading Europe.
Even if we have shut the door on invaders arriving in ballast water, a number of other doors remain open. I believe the most important one is commercial trade in live aquatic organisms. I'm referring to the importation and sale of live organisms used for ornamental ponds, as pets, for biological research and teaching in universities, and for human consumption.
A very large number of organisms are transported into Canada every year. I don't think most people appreciate how big that number is. For example, Dr. Nicholas Mandrak, at DFO, has found that over 2,000 species of fish were imported alive into Canada in a single year—in 2005. Most of these are freshwater fish. Very few, if any, of these species are regulated. In the Great Lakes, there are already 30 non-indigenous species that are assumed to have been introduced through the ornamental plant trade, the aquarium trade, or the bait industry. At least half of these species have had significant ecological impacts.
There are several imported species that have not yet invaded, as far as we know, that have been identified as being serious threats to invade and cause undesirable impacts. You have heard of one example, Asian carp, which actually consists of a few species, such as bighead carp, silver carp, and grass carp.
Most of the attention on Asian carp has been focused on the Chicago shipping canal as the potential pathway by which they can enter the Great Lakes from the Mississippi River basin. A more important vector may be live trade. Asian carp are being raised in fish farms in the southern United States and then transported into Canada to supply Asian food markets. Multiple times over the past few months, Canadian border security have stopped trucks from transporting thousands of pounds of live Asian carp across the border at Windsor, Ontario. I should point out that border security does not have a mandate to seize shipments of fish. They are merely cooperating with the Ontario government, which prohibits the possession of live Asian carp in the province.
At the federal level, live trade is completely unregulated as an invasive species problem. The Canadian Food Inspection Agency regulates several hundred aquatic animal species that are reported to carry diseases that pose significant economic or human health risks. Canada has no federal regulation that allows us to ban the importation of species based solely on whether they pose an invasion threat. We do not prohibit the importation of known invasive species. This is in sharp contrast with certain other nations, such as New Zealand and Australia, which have stringent biosecurity regulations based on risk assessments.
This brings me to my final point. The most cost-effective method of dealing with invasions is prevention, which requires early detection and rapid response. Unfortunately, there is no coordinated monitoring system in place to detect new invaders in the Great Lakes. There is no infrastructure for early detection and rapid response to an invasion threat. There is no federal policy to identify and regulate the relatively small percentage of incoming species that would likely be harmful to Canadian ecosystems. Until that situation changes, our natural resources will continue to be degraded by invasions.
That concludes my statement.