'%Healthy Reefs for Healthy People - A Guide to Indicators of Reef Health and Social Well-being in the Mesoamerican Reef Region%'%by Melanie McField and Patricia Kramer%

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FOCAL SPECIES ABUNDANCE

ORITY ON

S FOR HEAL

What

What Is It?

BENCHMARK

Focal species abundance refers to the abundance

No population decline from current

of key marine species of concern, including those on

levels. Assessments of sawfish and

IUCN's Red List of Threatened Species. (See Appendix

goliath grouper undertaken on a

3 for the list of threatened species found in the

regional scale.

regional

MAR).

TA R G E T

Examples of Mesoamerican focal species include

Stabilize

Stabilize populations to a level

the critically endangered hawksbill and leatherback

warranting removal from the IUCN

sea turtles, largetooth sawfish, goliath and Warsaw

Red List. For managed species (e.g.,

groupers, as well as the charismatic and threatened

manatee, hawksbill turtle), targets

manatees and whale sharks.

should meet stated management

Why Do We Measure It?

Why

goals. For threatened species without

management plans (e.g., whale shark,

The status of focal or "flagship" species is often

goliath grouper, sawfish), the target is

indicative of the condition of many other flora and

to have the regional abundance of each

fauna that rely on similar habitats. A decline in

species double over the next 20 years.

threatened species (e.g., whale sharks or manatees)

signals a potentially significant reduction in overall

RED FL AG

biodiversity for the region. Such losses may result in

Any increase in manatee strandings.

Any

direct economic losses as well, through accompanying

decreases in tourism value.

More than 10% reduction in turtle

nests in a single year or consistent

At least one large marine vertebrate has become

decrease

decrease for 2-3 years.

extinct in the last 50 years: the last Caribbean monk

seal sighting was recorded in the 1950s in Seranilla

Any consistent (2-3 year) decrease

Any

Bank, between Honduras and Jamaica2.

in whale shark abundance at

aggregations.

How

How Do We Measure It?

Manatee abundance is estimated by aerial surveys

Whale sharks are visually counted at aggregation sites

and direct observation.

in Belize and Mexico during aggregation periods. They

can be tagged with visual, acoustic or satellite tags.

Sea turtles are monitored by counting nest abundance

on beaches.

Goliath and Warsaw groupers and sawfish numbers

are too low to sample with traditional means. These

populations are monitored by surveys of fishermen's

catches.

Usefulne s s

Usefulness

"Charismatic megafauna" is how conservationists

often refer to the large, exciting animals, many of

whom now waver on the verge of extinction, capturing

the attention of the general public with their plight.

The focal-species indicator is highly relevant to

assessments of reef health, as the functional

importance of biodiversity is well recognized and

supported by the general public. The species discussed

in this profile are not all-inclusive, as all of the red-

Doug Perrine

listed species should be monitored and conserved.