usual in that these squid, while now far less numerous,
can still be found around the island.
Other fish that also showed huge recruitments over
a few months were Magnificent Firefish, Nemateleotris
magnifica, which had been fairly rare. The Hawaiian Bigeye (’aweoweo), Priacanthus meekeri, had a population
explosion in 2003; the previous one had been recorded
in the 1970s, which goes to show how many years apart
some of these events can occur. The point here is that
population studies on fish species cannot be done over
a few weeks or months, or even a couple of years; they
must be ongoing in order to accurately gauge how the
population can fluctuate.
This is a big hurdle for scientists, who often get funding for only a few field sessions. What we really need
is much longer-term studies of reefs to ascertain how
coral and fish assemblages can change over time. This
also leads to a need to understand fish recruitment. How
can we know if we are taking fish at a rate that will deplete the population significantly if we don’t know the
rates at which new fish are recruited onto a reef? The fact
that no tropical marine fish species has become extinct
in Hawaii in modern times indicates that the collection
of marine tropical fish is not unsustainable.
Does fish collection impact fish populations? Most
likely it does, but this depends heavily on the natural
abundance of a species, as well as how quickly it recruits
onto a reef. The question here should be not how much
of an impact is there, but rather, does the impact allow the population to maintain itself at
a sustainable number? One must also
keep in mind that many species of tropical marine fish, especially in Hawaii,
occur over a wide range of depths and
over a wide area of coastline. Therefore,
there are populations that exist in areas
either too deep for extensive collection
or in areas unsuitable for diving due to
waves and wind. These areas can act as
natural marine protected areas by supplying undisturbed habitat for breeding
populations whose progeny can restock
adjacent areas.
larger fish, such as jacks — not to mention parrotfish,
goatfish, and wrasses, which are also removed in large
numbers annually — which has an impact on fish populations below them in the food chain.
When it comes to sustainability in the aquarium industry, we are an easy target for those who wish to curtail our activities. Our position is indefensible so long as
we lack the data to make the case that we can operate in
a sustainable manner. Unfortunately, those who claim
unsustainability use fear, misinformation, partial facts,
ignorance of trade practices, and emotional arguments
as ammunition, but don’t seem to be hindered by the
lack of facts to support their positions.
The preservation of the Northwestern Hawaiian Islands through the establishment of a national monument is an important step in protecting the region’s reefs
in a condition as undisturbed as can be found in Hawaii.
Having this huge marine refuge can show us how much
has been lost in the main islands, particularly with respect to the larger fish species such as sharks and jacks.
Creating small marine protected areas that ban tropical
fish collecting, or imposing outright bans on tropical fish
collecting on all the islands, will have little impact on
these large fish populations that play such an important
ecological role on coral reefs, a fact that seems to be lost
on many of the opponents of aquarium fish collecting.
In my next column, I will look at some of the sustainability initiatives that are underway in the public
aquarium community.
Introduced Predators
There are several additional factors at
play in Hawaii, other than tropical fish
collecting, that could be impacting the
fish populations. Since the intentional
introduction in the 1950s of fish that
feed heavily on small fish, such as the
Peacock Grouper, Cephalopholis argus,
and the Bluestripe Snapper, Lutjanus
kasmira, their numbers have exploded.
The extensive sport-fishing activities on
the main islands have depleted stocks of
