Years ago I wrote a quick little piece detailing ten reasons why ferrets
could not go feral in California. In the piles of email I am trying to
catch up on, an anonymous person from California asked me to update the
list. Ok, I will, BUT, only one point per post, posted irregularly as I
have time and energy. I will NOT be providing references at this time
(to save bandwidth; references could double or as I cite, triple the length
of the post). IF, when the series is complete, there is a desire to
compile the material into some sort of reference, I will happily provide
a reference-filled (and edited together) version for use. At this time,
this is just designed to stimulate debate and discussion, NOT to be
downloaded for web or newsletter use.
PLEASE, I retain all rights; this is to be considered a "preliminary draft
only: do not cite, redistribute nor duplicate with the permission of the
author" version. This is a modified draft of a paper I am working on,
meant for journal publication. To make the text more readable, I have
simplified some parts and omitted others (hence the request not to cite;
simplification can lead to inadvertent errors), but in most cases, the
argument and points are identical between the two versions. Because I
basically have to do a rewrite to get the more scientific version
toned-down for a general-audience posting, some of the wording might be
rougher than in my scientific draft.
Ten Reasons Ferrets Cannot Go Feral In California (Actual working title:
The California Ferret Issue: Putting the "Con" into Controversy):
Introduction and Nomenclature
The California Department of Fish and Game (CDFG) has long posited the
domesticated ferret (Mammalia: Mustelidae: Mustela furo) constitutes an
ever present danger to the wildlife and livestock of the state of
California, and has fought expensive legal battles to retain their legal
jurisdiction over the increasingly popular pet. To this end, the CDFG
has emphasized the danger of the domesticated ferret being abandoned or
otherwise escaping captivity and establishing feral colonies. Chief among
the CDFG's evidence are the existence of feral colonies of ferrets in New
Zealand, a former colony on one of the San Juan Islands (Washington),
infrequent rescues, and sightings in several U.S. locations. The CDFG
position has increasingly come under attack by pet ferret owners,
biologists, politicians, and even a recent think-tank study. Currently,
the CDFG is embroiled in several intensive legal battles, costing thousands
of taxpayer dollars.
This paper will argue the CDFG position is a politically based decision
which neither relies on scientific protocols and procedures, nor on
empirical data which allows scientific falsification and review. Rather,
the CDFG argument is tautological in nature, relying on misrepresentation
and exaggeration to make it's point, and ignores contradictory data in
their preoccupation to retain legal jurisdiction of what is universally
recognized a domestic animal. To this end, I shall refute ten implicit
CDFG arguments, used to justify their ban of ferrets in the state of
California.
1. The ferret is the same animal as the European Polecat, so it can live
in a wild (feral) state.
While the CDFG has recently admitted on it's web site that the pet ferret
is domesticated, they still continue to link the domestic variant with
the ancestral progenitor and characterize both as blood-thirsty animals,
capable of invading and naturalizing in California, causing the destruction
of native fauna. Part of this emphasis is demonstrated by their constant
referral to the taxonomic binomial of the domesticated ferret as M.
putorius, even to the point of characterizing the use of M. furo as
incorrect. This emphasis is faulty on the following grounds.
First, the exact taxonomic position of the ferret is unclear. A review of
recent work by Davison et. al (1999) suggest the exact ancestral polecat
which gave rise to the ferret is undetermined. Under taxonomic protocol,
because it is unclear if the steppe polecat (M. eversmannii) or the
European polecat (M. putorius) or even some sort of hybridization of the
two is the progenitor species, the domesticated ferret's binomial should
revert to M. furo. SInce Davison's work directly compared the DNA of the
domesticated ferret to the polecats, it should be considered a refinement
over earlier work which only compared the karyotype, that is, the external
morphology of the chromosomes. In other words, since it is currently
impossible to prove which polecat gave rise to the domesticated ferret, it
is improper to assign any binomial other than the original M. furo.
Secondly, the emphasis on the ancestral species being the same animal as
the domesticated variant is inflammatory in the context of the issue
being presented. Using Wilson and Reeder (1991) as a standard for naming
species, not only is the domesticated ferret listed as M. putorius, but
the domestic dog is listed as Canis lupus rather than C. familiaris. In
one breath the CDFG ignores Wilson and Reeder, listing domestic dogs as
C. familiaris, but in the other, it chastises ferret advocates, insisting
Wilson and Reeder are the standard and ferrets are properly M. putorius.
This type of contradiction, for whatever actual purpose, presents an image
of an organization content to manipulate scientific nomenclature to further
political policy. It smacks of duplicity and manipulation.
Finally, the issue of scientific nomenclature towards domestic animals
is controversial. Currently, a petition is being considered by the
International Committee for Biological Nomenclature which would officially
revert the ferret's binomial to M. furo. Regardless of the ultimate
ruling, the protocols of naming a domestic species grant little recognition
to the process of domestication, which, as Darwin recognized, is a
human-selected form of evolution. Indeed, it is arguable that the gene
frequency shifts required for domestication, the morphological and
behavioral changes, and the reproductive isolation would exceed those
criteria for recognizing a new species, if the animal in question were
wild. Clearly, this issue needs further study and comment beyond the
scope of this paper.
In the context that the domesticated ferret's ability to naturalize in
California, the frequent mention of the domesticated ferret's scientific
binomial as being the same as the ancestral progenitor serves to link the
domestic species with the wild one in such a way that the uninformed or
unwary might consider the two "identical" animals. It is a simple trick;
guilt by association. The emphasis is designed to create an
unsubstantiated bias towards the pet ferret by creating a false perception
that the polecat and ferret are the same animal. Once that perception
is created, and guilt by associated is assumed, then the CDFG cites
characteristics more common to the wild progenitor than to the domestic
variant as dangerous behaviors. Without using empirical support to back up
the claims, predatory, reproductive and dispersing behaviors are assigned
to the domestic variant. This isn't only manipulative to a scientifically
uninformed audience, but it is also bad science.
Regardless of the ultimate classification of the pet ferret, there is no
evidence presented that a domesticated variant of a wild species can go
feral simply because the ancestral progenitor lives in the wild condition.
The ability to naturalize and create feral populations is dependent upon a
myriad number of factors, such as competition, local guild structure, risk
of predation, prey type and availability, to name a few. But one trait
never mentioned in the introduced species literature for increasing risk of
introduction is the sharing of species names between the domestic variant
and the wild ancestor. Indeed, it is likely that the factors allowing
successful exotic species introductions are so complex as to render useful
predictions of naturalization impossible.
The CDFG's inordinate focus on the domesticated ferret's Linnean binomial
serves no useful purpose other than an apparent attempt to manipulate and
confuse. Regardless of the ultimate taxonomic classification of the
domesticated ferret, the discussion has no bearing on the ability of a pet
ferret being able to successfully introduce itself into the wild. The
comparison is inflammatory, and when being used to influence political
positions, it is simply unethical.
Bob C and 15 Mo' Furrowing Pharts
[Posted in FML issue 3163]
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