The Custom-House

Discouraging Invasive Hitch-hikers

Ships carry ballast water to manage their stability with different cargo configurations.  When they pick up ballast water in one port and carry it to another, they also can carry along species that haven't previously been present in the destination port.  These invasive species can cause a lot of problems.

Researchers at the University of Michigan are working on a "ballast-free" ship to discourage this sort of hitch-hiking ('Ballast-free Ship' Could Cut Costs While Blocking Aquatic Invaders, ScienceDaily, March 27, 2008).  The system works by continually exchanging ballast water so that the water in the ship is always local:

The Attack of the Giant Alien Carp

You try to do the right thing - clean up a polluted river - but that just creates an opportunity for an invasion by giant alien carp - only the Army, with an underwater electric fence, stands a chance of stopping them: An Underwater Fence to Stop Invasive Species (Kari Lydersen, Washington Post, July 16):

Michigan tries to stop invasive species

Douglas Belkin reported on a trade related issue this week - invasive species: What's Black and White and Has the Great Lakes Seeing Red?. Invaders Like Zebra Mussels Prompt Michigan to Require Clean Ballast; Shippers Sue  (Wall Street Journal, July 5). 

He focused on zebra mussels in the Great Lakes:

On the North Pacific Great Circle Route

A week or so ago, The Economist had an article on recent shipwrecks and shipping accidents on the great circle route between the U.S. West Coast and East Asia (The North Pacific great circle route. A cold coming We had of it., Jan 18 - subscription required). 

The accompanying map showed that the shortest distance between East Asia and the Canadian-American Pacific Northwest runs through the Bering Sea:

Vessels traveling between East Asia and the North American West Coast actually pass both north and south of the Aleutians.  My understanding is that most vessels on the route north of the Aleutians pass from the North Pacific into the Bering Sea at Unimak Pass, to the east of Dutch Harbor, rather than to the west as shown.  The Coast Guard has begun monitoring traffic through the pass.  I think vessels are passing through it at the rate of about 3,100 vessels a year. 

The Economist article gives me an excuse to post some striking photos of the M/V Cougar Ace.

International trade and externalities

Michael Margolis and Jason Shogren point out ("How Trade Politics Affect Invasive Species Control", Resources for the Future discussion paper 04-07) that international trade itself may be a source of negative externalities. Unpleasant invasive species (think zebra muscles in the Great Lakes) may come in the cargo, or in ship ballast water; the movement of cargo may create pollution externalities; trade activity may provide opportunities for the movement of contraband or terrorists. From the abstract:

"Trade has become the main mode of transport for many invasive species including diseases and agricultural pests. Most species are brought to their new homes unintentionally, which constitute a market failure rooted in international trade. Unless it is practical to drive invasion risk to zero, the external costs may justify a tariff..."

The problem is that in a world with interest groups, and interest group contributions to politicians, "The invasive-species tariff is set higher than it would be if government were independent of rent-seeking contributors." "The informational needs required to distinguish disguised protectionism from legitimate public-goods protection are formidable."