Page 39 - climate-change2013

4. Shifts in species The parrot fish, Sparisoma cretense
distribution patterns more common along the eastern
and southern Mediterranean coasts
is moving towards northern areas.
Rapid and significant shifts in the ranges of non-native
fishes, crabs and other invertebrates have been record-
ed in the Mediterranean in recent decades (CIESM,
2008). Native species are also moving northwards and/
or to greater depths in response to warmer waters. Be-
sides, the Mediterranean is threatened by introduced
non-native species. Some of these species have warm-
water affinities and the rising temperatures could be
favouring their spread (see Case study 4). Overall the
shifting distribution of native and alien species may
modify species interactions (competition, predation,
etc.) and may ultimately result in the loss of species,
including protected species, and changes to local com-
munities.
Shifting distributions can therefore lead to a number of
new challenges for MPA managers, such as the arrival Photo: A. Can - www.alpcan.com
of invasive alien species, the loss of protected species
or major changes in marine ecological communities.
from the seabed to 30 m depth, which are surveyed
Long-term data can reveal the arrival of any warm-water by means of appropriate techniques (snorkelling and
and alien species or shifts in the distribution and abun- diving). The methods are based on replicated visual
dance of cold-water species within MPAs. searches lasting for a fixed time and covering a specific
stretch of coastline or seabed, where an observer re-
INDICATOR cords the presence or absence of species and makes
a semi-quantitative assessment of their abundances
Changes in ranges, using pre-determined categories: abundant, common,
distributions and abundance of frequent, occasional and rare (the ‘ACFOR’ scale).

temperature-sensitive species The protocols have the objective of recording:

1. Range extensions of native warm-water species;
Species that tolerate a wide range of temperatures
may not exhibit a response to increasing sea-surface 2. Range contractions, ‘deepening’ and/or decline
temperatures over a short time period. Some species, of native cold-water species;
however, are more sensitive and respond quickly, and
their ranges may shift further north or to greater depths 3. New introductions and range extensions of tropi-
as a result of thermal stress caused by the rising tem- cal non-native species.
peratures.
A guide to identification and monitoring protocols for
PROPOSED MONITORING PROCEDURE marine invasive species of tropical origin can also be
The presence and abundance of climate-sensitive spe- found in the recent publication Monitoring marine inva-
cies should be monitored in each MPA over the long sive species in Mediterranean Marine Protected Areas
term to detect range shifts. These results should be (MPAs): A strategy and practical guide for managers
compared with those from other MPAs and across a (Otero et al., 2013).
network of sites. Such monitoring data will constitute
the MPA’s baseline for future reference (see Case Study In addition to methods for monitoring and tracking inva-
5). sive species, another technique that could be used to
track particular biodiversity changes in benthic commu-
The aim of the survey is to monitor the presence and nities along a depth gradient is the use of ground-based
distribution of key climate warming indicator species photo points (see MPA Case Study 6). This method can
across the Mediterranean or over a smaller region. The produce a rapid, cost-effective assessment of trends in
methodology adopted by the CIESM Tropical Signals the biodiversity of benthic communities over time and
Programme uses three types of protocol, suited to the show whether climate change is causing significant
intertidal zone, shallow waters (0–3 m) and the zone shifts in species distributions.

MEDITERRANEAN MARINE PROTECTED AREAS AND CLIMATE CHANGE: A GUIDE TO REGIONAL MONITORING AND ADAPTATION OPPORTUNITIES 37