Biology Reference
In-Depth Information
Walters et al. (2006) surveyed 47 salt water aquarium retailers in central Florida.
Fifty-three percent sold
Caulerpa
, but none had
C. taxifolia
. A total of 9 species of
Caulerpa
were available for sale in central Florida.
Electronic commerce (e-commerce) increasingly is the primary, if not only, shop-
ping venue for aquarium hobbyists. From 30 internet commercial retailers and 60
internet auction sites (eBay), Walters et al. (2006) made online purchases of 12 spe-
cies of
Caulerpa
from 25 US states and Great Britain (Walters et al. 2006; Stam
et al. 2006). Fifty-two percent of the states were landlocked, suggesting prior transport
by hobbyists or the US postal/private shipping services. Walters et al. (2006) pur-
chased
Caulerpa taxifolia
only once from a commercial online retailer when listed
as “green feather
Caulerpa
” on the seller's web site. The purchased
Caulerpa
was
shipped from a southern California retailer to Florida in November 2004 raising
concern that this purchase might be the first documented case of human transport of
the invasive strain of
C. taxifolia
. It, however, turned out to be a specimen of
Caribbean origin based on the DNA sequence analysis (Stam et al. 2006). Hence,
this clone of
C. taxifolia
was somehow transported from the Caribbean basin to
California and then to Florida. On eBay you can buy entire aquarium setups that
need to be collected in person. Walters et al. (2006) noted 13 auctions representing
10 states, but did not acquire
C. taxifolia
via this dispersal mechanism. They did,
however, purchase
C. racemosa
and
C. mexicana
with one aquarium purchase.
Live rock is another way
Caulerpa
can be globally distributed (Walters et al.
2006). Live rock is coral (or other substrate) that is either directly quarried from
reefs or kept in waters under aquaculture conditions to allow a diversity of organ-
isms to attach. Live rock is extremely popular with hobbyists because the rock can
be inexpensive and with each purchase there is the possibility of receiving a diver-
sity of novel species. Zaleski and Murray (2006) found that 94% of southern
California shops sold live rock and 18% of these had visible growth of
Caulerpa
on
them. Walters et al. (2006) purchased live rock from ten retailers in central Florida
and had small quantities of rock (
10 kg) shipped to a Florida address from
11 internet retailers and 9 auction sites. After a minimum of 1 month in quarantine
culture,
C. racemosa
was visible on three purchases of live rock, and
C. sertulario-
ides
,
C. mexicana
, and
C. verticillata
were each found on one purchase. No
C. taxifolia
was transported via live rock in this study (Walters et al. 2006).
≤
15.5
Control Methods Used to Try Dealing
with Recent Invasions
There is significant pressure on marine managers to immediately remove or control
any invasive marine species when an incursion occurs using the best science available
(Bax et al. 2001). Thresher and Kuris (2004) list issues with the marine environment
that make managing marine invasions very difficult. These include the following:
(1) the ocean is perceived as an open system, (2) the public perceive oceans and coastlines
as pristine, (3) a defeatist attitude by coastal managers, (4) limited knowledge about
