The W's of a species invasion

When people go beyond the typical "oh you are studying marine biology that really cool" talk (something that I should write about at some point) and want to know exactly what I am doing with my summers, I usually say that I am studying a species of seaweed that is not where it's supposed to be. Most people have never heard of the concept of introduced or invasive species before, so the conversation usually turns in that direction and only occasionally goes back to my research.

But these conversations makes me wonder how I can talk about what I do in a bit more depth, while keeping it interesting enough for people who think algae is sushi and muck on fish tanks. I am going back to a primary school English composition framework because I realised that studying a new species invasion is a bit like the compositions we were taught to write as seven year olds - you have to address the same spread of questions. Also, if you can explain your science to a seven year old then you either have a brilliant seven year old or you have achieved relatively good communication of your science. (Which is why you probably have to test it out on more than one seven year old.)

So here is a brief summary of the questions we are asking, in terms of the good old 5 W's:

1. Who

Who is the invasive? - This question is a little bit out of order, since we had to figure out what the algal species was in order to determine that it was a new invasive species. This question was answered last summer, thanks to Craig Schneider at Trinity College who first documented the presence of Heterosiphonia japonica in southern New England.

Mr. Hetsiph makes friends with a kelp stipe.

2. Where

Where is it now? - We have some idea of this from last summer and a tentative northern range limit, and there are people further south who are looking out for its spread.

Where did it come from? - Most likely from European waters, where it is also invasive, but possibly from its native region in the North Pacific. This could probably be figured out using genetic comparisons of the New England populations with potential source populations from different places, but that is out of this lab's area of expertise so it is probably a question for someone else to answer.

3. When

When did it get here? - Still unknown, but certainly sometime before summer 2009, when it was first found and identified in New England. We don't know if it was introduced only once and just spread rapidly, or if it was introduced multiple times in multiple locations.

4. What

What is it doing here? - This is where we're at now. What kind of interactions does our invasive species have with the native community of algae (competition for space and nutrients, maybe?) and the herbivores like snails and amphipods? To try and answer some of these questions, we are conducting field surveys of algal species and abundances, which will lead into field and lab experiments later on.

"What does this mean for me?"

5. Why

Why does this matter? - Probably the most important question of all. Why should anyone care? Well, invasive algae have been an issue in the western Atlantic for some time and some have significant negative impacts (e.g. Codium fragile). Coastal management agencies are interested in knowing the potential impacts of the invasion on coastal health, water quality, etc. And because of the relatively early stage of this species invasion, what we learn about Heterosiphonia could contribute to a more general understanding of what makes an invasive species successful, and how invasions spread.

That's it for now, tomorrow I shift gears completely and head for somewhere a little more exotic. I fly from Boston to Quito, Ecuador, and then take a domestic flight into Baltra in the central Galapagos archipelago on Thursday. Hopefully there will be more blogging from the land of the tortoises.