My name is Ladd Johnson. I'm a professor at Laval University, a member of Québec-Océan, and also—and I don't think Dr. Ricciardi mentioned this—a member of the Canadian Aquatic Invasive Species Network.
I'm capable of giving this in French, but I'm a little nervous and I think it would be better for everyone if I continued in English. My apologies to the francophone people here. I would be happy to handle questions in French, but I think for everyone's benefit I'll continue in English. I've also been in Chile for the last four months on sabbatical, so Spanish words are running through my head. I've also been travelling for the past two days to get here, not specifically to get to this meeting, but I'm a little bit fatigued from that as well.
After I learned Dr. Ricciardi was going to be presenting, I knew he would cover the details, the facts, and the trends very well for the Great Lakes, because that is really his speciality. I also have worked on invasive species for the past 20 years, but I would argue that this is my applied nature. I also work on fundamental aspects of ecology, and I work in marine systems on invasive species as well. So I decided, when learning Dr. Ricciardi would be here, that I would orient my presentation more towards conceptual things, particularly the role of uncertainty in our dealing with invasive species.
Dr. Ricciardi tells me I should speak more slowly. I will try to speak more slowly.
If I can go to the first slide, I would say everywhere in the process we have uncertainty. Often invasions are done in three phases. Where there is an introduction, we have a lot of uncertainty about the vectors, the types of vectors that are involved, and their activities. We've made great progress, but we still have a lot unknowns about that.
For the establishment, often the second phase of an invasion, there are new ideas emerging about propagule pressure, the number of propagules necessary to establish a population. But we are still learning a great deal about that and an effect, known as the Allee effect, requiring a certain critical number.
A long time ago I published a small piece about mussel myths and the “Noah fallacy”, which dealt with the idea that it would only take two zebra mussels to start a new population. I think we all know that's not true. The Noah fallacy was the idea of Noah's collection of pairs of animals. We know now that it takes a substantial number of propagules. We still do not know how many. It varies from species to species. Of course this is part of the science we're doing to investigate this.
Next, we would have ecological and economic impacts. Again, as Dr. Ricciardi mentioned, many of the species have not been well studied. We certainly know the best cases. There are many stories of that. They are very rarely quantified in terms of being able to compare for cost-benefit analyses.
Finally, I will talk about our actions. This is where I'm hoping to inspire you, because you people are the ones who will be taking action on this at a government level. These actions include assessing how good a job we're doing. Many times we do things that one would say are feel-good measures; we think they should do well, but then we never assess whether or not they've actually accomplished our goals. In monitoring, often our monitoring efforts are inadequate. We hope we can detect things, but we do not really have certainty in doing that. Finally, in our response, sometimes I believe we are afraid to make responses or take actions or decisions because we are not certain as to the outcome of those actions. I'll develop those a little later.
I will talk about government actions, because you are in the government, and we are here to help you make decisions. Of course we need to fund more research—that's what any good scientist would say in order to obtain more funds—but I would argue that we need to specialize those in the invasion process itself. Oftentimes we study the impacts, but we're not really looking at how they get here and how they become established. On cost versus benefits, as hard as it is sometimes to quantify ecological and economic impacts, we need to somehow obtain means of comparing things so we know what the costs of our actions are, and the costs of our inactions.
We need to turn our uncertainties into probabilities, because that's really what uncertainty is. It means that something might not happen. Probability is just a way of quantifying that.
Secondly, I mentioned participating in more research. That basically means funding government agencies to work more closely with government scientists. I think the network that Dr. Ricciardi and I are involved in is an excellent example of how cooperation between DFO scientists and university scientists has led to many good outcomes.
We need to also create a regulatory structure to prevent future things, much like the ballast water exchange program that's enforced rigorously, because oftentimes there is not proper enforcement after regulations are on the books. Dr. Ricciardi mentioned more monitoring so we can detect incipient populations and invasive species and react.
We need to have plans in place for responding so we can assess whether we should take actions, and what types of actions we should take—containment or eradication, or perhaps just control.
Finally, of course, we need to cooperate. The obvious one is Canadian versus American interests, but there are other stakeholders that need to be involved, such as the public, commercial enterprises, etc.
Just to give an idea of the costs and benefits, I made a little table here. I don't want to go into too much detail, but we need to start filling in some of these blanks. In proactive management, such as ballast water management, where we take no action there is no cost, but there are negative effects, if you don't mind me saying. We don't know if the probability is 100%, because maybe they'll never come. Maybe we'll be lucky and a species will never appear.
If we do take action it will cost us money, and we can quantify that, but we cannot quantify the benefits. That's again where we need more science in ecological economics. The probability is that we do not know, and perhaps our actions will not help.
On reactive things, once a species has become established, taking no action doesn't cost us anything, but there will be definite negative benefits. The probability of that is 100%. Action will take money, but the benefits will be positive in reducing the impact of invasive species. Again, we are not certain if those actions will actually accomplish what we hope for.
I'll give you one example here where we have made progress. A recent study showed the costs and benefits of doing prevention and control. It found that managers should take the risk of trying to prevent, because that will yield better economic benefits for society in the long term.
Risk assessment is important, and I want to mention a few things we need to give attention to for establishment. We need to identify the species that are likely to come; the regions from which they might come; the things that might bring them and the paths they might take; the places they might show up—often known as hot spots in our business; and the times they might show up—often windows of opportunity when things might become established. These are all part of refining our science.
I want to finish by talking a little about secondary dispersal, because I think it is the biggest problem facing our science. Preventing invasive species from becoming established initially is obviously a good idea. It's the best way to prevent problems, but what do we do after they come here?
The problem is that once secondary spread begins, human-mediated vectors can continue the spread, but natural ones can as well. This leads to a mentality of inevitability—that it's a lost cause and we have lost the war. I think this is a rather defeatist attitude, and the goal has to be slowing the invasion instead of stopping it.
Even if you think it's inevitable, slowing things down will accrue benefits over time. If it didn't accrue benefits over time people wouldn't be worried about the spread. People are always worried about the spread, so if we can slow down the spread we will accrue benefits over time.
I'll give you the case study on invasive tunicates in Prince Edward Island, where I am working. We have invasive tunicates located in just three or four bays in the east end. I'm sure all of the mussel farmers on the rest of the island would like them to stay in the east end. I think that is a manageable goal, and possible to achieve.
Finally, I think our goal is to predict invasions better and respond more rapidly. We need to accept uncertainty in more general terms and try to translate it into probability. We need to seek more data, but prioritize it toward the data that is more essential for decision-making. Taking action is an important element. We can't sit by and wait. We also have to accept that we will make mistakes.
Thank you very much.
