Environmental Engineering Reference
In-Depth Information
would expect smuggled imports to exhibit a higher risk of harboring NIS than legally
imported goods. In short, it is conceivable that commodity taxes and strict port inspec-
tions may actually raise NIS damage in the presence of smuggling. This has some of the
same
avor as Fischer's (2004) argument that sanctioning some trade in endangered
species parts may reduce stigma from illicit trade, with feedback e
fl
ff
ects on poaching
rates overall.
Poor observability creates an obvious obstacle to liability rules. As Shine et al. (2000)
note, for large captive animals it may be possible to establish compulsory registration
and marking systems, so that the owner of a released NIS can be easily identi
ed. But for
most NIS this is not possible. As summarized by Europe's Standing Committee for the
Convention on the Conservation of European Wildlife and Natural Habitats,
fi
[w]here invasive alien species (IAS) cause damage, conventional approaches to liability are
usually dicult to apply. This is partly because of diculties in proving causation and/or fault
(time lag, scientific uncertainty, number of users involved) and partly because many existing IAS
were introduced to the environment in the past by businesses operating under legal standards
and permits. (2003, p. 20)
Separability
Even if detection is easy, if a product and its contaminants are easily separated it might
make more sense merely to undertake processes that achieve separation, even for prod-
ucts that may be clean from the start. In some cases this can be achieved by imposing
product standards, as mentioned above.
Wilson and Anton (2006) examine the substitutability of mitigation strategies, such as
treatments that reduce the NIS infection rate, and border measures, such as tari
s and
import bans. Calibrating an example of preventing foot and mouth disease from entering
the USA, they
ff
nd that mitigation strategies (culling and vaccination) generate net
welfare gains and that it is optimal to apply mitigation strategies
fi
fi
rst, complemented by
a tari
if necessary.
Alternately, process standards may be in order, such as requiring products to be irradi-
ated as with US imports of mangoes from India. Similarly, many countries (in compli-
ance with WHO and International Civic Aviation Organization guidelines) engage in
'disinsection' - the spraying of airline passengers with insecticides to reduce the risk of
importing harmful NIS (Gratz et al., 2000).
As is well known from the literature on environmental regulation, performance and
technology standards are blunter tools than emission taxes or tradable permits. The
problem with applying direct contamination taxes for NIS is the observability trait
described above. Some researchers have proposed a variation on the tradable permit
theme. For example, Horan and Lupi (2005) propose tradable risk permits; risk levels
would be judged based on biosecurity measures undertaken.
Fullerton and West (2002) point out that in cases where the undesirable attribute is
unobservable, employing a series of subsidies to inputs complementary to abatement,
taxes on inputs that are substitutes to abatement, as well as a tax/subsidy to the product
overall, can act as an equivalent to a tax on emission intensity. In the case of traded prod-
ucts likely to harbor NIS, the appropriate panoply of substitute instruments may include
an import tari
ff
ff
that is partially rebated depending on the individual exporter's e
ff
orts to
'pre-clean' products as evidenced by undertaking certi
fi
ed management practices.
