WWF Shining a spotlight on the biodiversity of ... - MarineNZ.org.nz

Executive Summary
The distinctive nature of New Zealand’s
marine biodiversity has led to its
identification by <strong>WWF</strong> as one of 238
ecoregions (collectively known as the
Global 200) that are global priorities for
conservation action. An ecoregion is a
large area of land or water that contains
a geographically distinct assemblage of
natural communities that share a large
majority of their species, ecological
dynamics, and environmental conditions.
Planning at the large scale of the ecoregion
is consistent with an ecosystem-based
approach to management. The ecoregion
approach promotes conservation efforts in
accordance with ecological processes and
systems rather than along administrative
boundaries, thereby creating new
conservation opportunities.
With the long-term aim of contributing to
marine biodiversity conservation, <strong>WWF</strong>-
New Zealand established the New Zealand
Marine Ecoregion Initiative in 2003,
which is part of <strong>WWF</strong>’s global approach
to mobilise conservation efforts in priority
regions of the world. In response to
the need for an independent, scientific
assessment of New Zealand’s marine
biodiversity, <strong>WWF</strong>-New Zealand convened
marine scientists for an expert workshop
that was held from 27-28 May 2003. The
22 workshop participants, who came
from around the New Zealand region,
hold expertise in taxonomy, ecology,
oceanography, and conservation. They
collectively have specialist knowledge
across a wide range of marine organisms
and habitats in New Zealand.
During the workshop participants divided
into three subgroups that corresponded
with the types of biota for which they
had specialist knowledge: cetaceans,
seals, and seabirds; fish; and benthic
invertebrates, algae, and plants. Guided
by a set of criteria that they had developed
in the first session of the workshop, and
furnished with bathymetric maps of the
New Zealand region, the participants
delineated key areas for the biodiversity
of their respective biotic groups. Each
area was coupled with a description of
its physical and biological attributes, the
state of information, and references to the
literature. Biodiversity features that do
not lend themselves readily to discrete
geographic representation were reported,
but were not illustrated on the maps. The
oceanographers worked separately to
report on the physical processes operating
in New Zealand’s marine environment.
Experts identified areas of deepwater
emergence in Fiordland and Marlborough
Sound where species are found at
unusually shallow depths due to the
unique physical characteristics of these
environments. They noted the high
productivity of the hydrographically
complex Chatham Rise, the remarkable
invertebrate diversity of Spirits Bay, and
the expanding coverage of mangroves
in northern New Zealand. Seabird
experts highlighted the importance of
the subantarctic and Chatham Islands
as global hotspots for bird diversity, and
the importance of migration corridors
around New Zealand. Marine mammal
experts marked the canyon and trench
systems running from Kaikoura Canyon
northwards as attractive foraging areas
for deep-diving cetacean species, such
as sperm whales. Overall, the work of
the marine scientists shines a <strong>spotlight</strong>
on key areas for biodiversity in New
Zealand’s marine environment, contributes
to the greater body of knowledge of the
ecoregion’s marine biodiversity, and
makes such knowledge available in a
summarised and accessible form.
The results of the workshop are
constrained by the limited biological
sampling that has been conducted in New
Zealand’s marine environment. In addition
to identifying areas that are thought to
be important for marine biodiversity,
workshop participants identified some of
the gaps in the knowledge base. Much
effort has been put into research on the
spatial distribution of marine organisms,
but there is still under-representation in
sampling efforts, such as for all species
and habitats deeper than 1,500m, and for
specimens smaller than 2mm. Information
deficiencies for ecosystem processes,
such as trophic interactions, population
dynamics, and recruitment are even
greater. Participants expressed particular
BIODIVERSITY – NEW ZEALAND’S MARINE ECOREGION ■ 3