Handling Invasive Species: studies look at treatment and commercial enterprise

Invasive species continue to pose problems around the world - from relocated fish and land animals to plants to even infectious diseases.  In the oceans, invasive species can prove to be both disruptive to the marine environment and a potential hazard to humans as well.

Two recent scientific studies, one in Emerging Infectious Diseases and the other in Marine Pollution Bulletin, looked at the issue of ballast water that is taken in and released by tankers and freighters in ports all over the globe.  This exchange of water to maintain a safe balance to the ship as it loads or unloads its cargo has introduced a variety of unwelcome guests including mussels, seaweeds and algae, and even cholera.

Sometimes the ballast exchange takes place in deep enough water so that its contents are sufficiently dissipated.  But in shallower water, pathogens as a product of urbanization and sewage can either come aboard or be expelled and soon brought into shore via swells and currents.

One solution is to treat the ballast water on board the vessel.  However, ports and cities are then dependent on the ships having the proper equipment and using the methods effectively to do the job.   The other possible approach is to develop an onshore treatment process wherein the ballast water is pumped ashore for treatment and then pumped back to the ship as needed, rather than having the entire ballast exchange take place in open water.  A better idea perhaps on paper, but it requires  considerable investment in equipment and the design of each port must be carefully studied to determine if and where the systems can be installed.

However, compared to the financial losses incurred by invasive species from disrupted commercial fisheries to clogged water inlet/outlet pipes to disease outbreaks, the costs of advanced onshore treatment systems could prove to be a bargain.

Another study, written up in Conservation Letters, examined the issue of whether consuming an invasive species as a possible food source could prove to be an effective means of populations.  Why beat it, just eat it.

This has been the approach taken in areas where the Humboldt squid has moved in, shifting the fishermens catch from local commercial fish stocks to all squid.  And in the Caribbean and the eastern Florida coast, where the lionfish population has exploded recently from its accidental introduction several years ago, attempts are being made to develop a taste for the South Pacific reef fish's meat among local sharks and even with the human population (a bit tricky to prepare but, I have been told, quite tasty).

The study, however, notes the dilemma that this approach can cause through the production then of a viable market.  An invasive species could turn out to be a commercial success and where there is commercial success there can be the desire to maintain or even expand it.  Suddenly, the invasive species becomes a profitable friend to man - at the expense of the marine environment it is affecting.  The ultimate insult would be that an effort could be made to protect the species for the sake of its commercial value - a complete reversal of the original concept of reducing or eliminating the population through harvesting.

The introduction of commercial enterprise and consumption in the control of any invasive species must be undertaken with a clear understanding by government and regulatory agencies as to the underlying purpose of taking such a step.  Either supported by scientific research or even just the common sense that every invasive species is a Pandora's box of unknown consequences, decisions must be thoughtful and well-informed.

Source: Emerging Infectious Diseases 18(10)
Source: Marine Pollution Bulletin 64(11)
Source: Conservation Letters 5(5)
          

Right Whales & Sound: study indicates ship noise impacts whale communications

The North Atlantic right whale is one of the world's most threatened whales.  Listed as endangered by the IUCN and the U.S. Endangered Species Act, its current population worldwide is perhaps only 550.  Once heavily hunted by whalers for its rich bounty in whale oil (hence the whale's name), today the whale is threatened by derelict fishing nets, known as "ghost" nets and by collisions with large commercial ships.

Right whales feed in the cold waters from New York to Nova Scotia, then migrate southward along the U.S. coast to Georgia and Florida to give birth.  Unfortunately, they do this in the midst of busy shipping lanes.  Whales have been sighted with large scars on their backs from encounters with ship propellors.  Speed regulations and policies have been put in place to have ships keep a close watch for whales and shipping lanes have been re-routed as needed during certain migratory periods.

However, according to the conclusions of a three-year study by the National Oceanic and Atmospheric Administration and the Stellwagen Bank National Marine Sanctuary, located at the mouth of Massachusetts Bay, large commercial ships are imposing another threat upon the right whales: noise.

The sound of the ships, in particular the bubbles produced by the propellors, is of sufficient magnitude as to significantly reduce the ability of the whales to communicate with each other.  In the rich feeding grounds off Massachusetts, the whales communicate to find food, navigate, mate, and just engage in small talk.  The intrusion of the ship noise could impact the whales ability to hunt for food - they often communicate to coordinate their hunting efforts - and this could lead to a lower calorie intake which, in turn, can lead to a reduction in reproductivity.

From 2007 through 2010, researchers study the noise levels and the communications of nearly 90 whales, using underwater recorders place on the bottom in the sanctuary.  It was determined that, compared to 50 years ago, up to 67 percent of the whales' "communication space" in the sanctuary and surrounding waters has been lost.

While other studies have taken place to confirm a detrimental effect, the researchers say that a considerable amount of additional research is required to truly quantify what impact the change in the whales communication will actually have on their health and well-being.

"We still need to know what that loss of communication means," said Leila hatch, marine ecologist with the sanctuary and lead author of the study's report published in the Conservation Biology journal.  "Those are big additional leaps we need to make. We're looking for the links. All behavioral changes usually have some cost. It may be that animals have some flexibility in what they can do. We have to remember, though, that they are constrained, by cost in energy [used] and by physiology, like how loud they can go" to compensate for the ship noise.

Hopefully, further study will provide the answers to steer ships, literally and figuratively, in the right direction.  Can the whales adapt to their noisier surroundings?  Or can ships alter their behavior - a challenge given the great distances that sound can travel underwater.

"We certainly don't understand how exactly this sort of problem will affect the animals, or what it will disrupt. It seems highly likely that not being able to hear from the distances they once did, for which they became adapted, would seem to have a detrimental effect, " said Charles Mayo,director of right whale habitat studies at the Provincetown Center for Coastal Studies.

Source: Cape Cod Times

Galapagos Islands: hi-tech GPS comes to the aid of marine park management

The Galapagos Islands - an oceanic oasis that was one of Darwin's key research sites for his seminal work on evolution - is feeling the pressure of its unique status. With increased tourism and island population, combined with international demands for seafood, the Galapagos has been showing signs of this negative impact on its natural resources.

The Galapagos Marine Reserve (GMR) was created in 1998 to provide protection to the islands' surrounding waters. And in the next few months, through the support of Conservation International and WildAid, the GMR will be taking a hi-tech step forward in managing major ship traffic in the area.

Utilizing GPS satellite tracking equipment, the activities of ships greater than 20 metric tons will be monitored by the Galapagos National Park Service (GNPS). This will provide the GNPS with greater ability to manage and regulate ships in no-take zones, tourism itineraries, and commercial shipping. Besides "tagging" ships, the computer-based system will enable the GNPS to tag and track migratory species and monitor environmental/climate changes.

Hats off to Conservation International and WildAid for supporting this important example of cost-effective marine research and management.

#6 in CO2 Emissions: cruising the seas out of the spotlight

When we consider the impact of global warming and climate change on the land, air, and sea, we often think of the combined CO2 emissions generated by different nations and their various commercial and/or public sources. But do you know what ranks as the 6th highest producer of carbon dioxide, just behind the 5 nations with the largest combined output of all sources?

Global shipping.

That's right. Right near the top of the list of major CO2 polluters. And it continues unregulated by any U.S. or Kyoto Protocol limitations. Why? Well, for one, it's a bit removed from the public spotlight, cruising the seas as it were, underneath the radar of public awareness. And for another, the shipping industry is both a fragmented and powerful commercial force that requires major international intervention to bring it under control.

What is there to regulate? Engine types, fuels, proper operational maintenance, emission standards - in many ways, what we do (or should be doing) regarding auto or factory pollution can be applied to shipping.

If we in the United States can get the EPA on board, this can be a major first step not only for the U.S. but for the world as it can set a new standard, particularly if the United States seriously considers getting back in lock step with the rest of the industrialized or developing world and considers aligning itself with the Kyoto Protocol or its possible future manifestations.

To that end, Earth Justice, Oceana, Friends of the Earth, and the Center for Biological Diversity have petitioned the EPA and, due to a lack of response by the EPA, are preparing to take legal action. To learn more about this issue, click here.