'%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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The MBRS protocol, in which clay tiles are attached to

Melanie McField / WWF

a PVC array, includes a detailed method for monitoring

with settlement plates8.

Usefulness

Coral recruitment is a critical component of ecosystem

health, particularly during times of reef recovery from

major disturbances (as we are now experiencing in

the MAR). Recruitment studies allow us to look to the

future.

The monitoring methods require a moderate to

high level of expertise to correctly identify the small

recruits. Some training

has been offered by

Suzanne Arnold

the Global Environment

Facility (GEF) / World Bank

Targeted Research &

Capacity Building Program

to expand their data

collection effort.

Settlement plates provide

One study on a Glover's Reef Atoll patch

more information on

reef reported a 53% decline in coral recruits

initial settlement patterns

and a corresponding 48% decline in coral

(especially smaller class

cover between 1998 and 1999, following

sizes) than do studies of

the 1998 coral bleaching event10. The low

recruitment onto natural

recruitment density in 1999 was attributed

reef substrate. However,

to a loss of corals (existing recruits in 1998

plate studies often require

and larger mother colonies), potentially reduced

a greater commitment of time, expertise, and money.

fecundity resulting from bleaching and scouring stress

Under the MBRS protocol, recruitment is a Level II

from Hurricane Mitch, and increased macroalgae.

(more difficult) indicator, and few MPAs have found

time to include it.

The 2006 regional AGRRA assessment greatly adds

to the regional pool of data available on recruitment.

Measuring recruitment on the natural reef substrate

provides a more realistic picture of recruitment

Data

Data Needs

success than do plate-based studies. Studies on

natural substrate include the effects of natural

No recruitment data are yet available from the MBRS

mortality levels, which are influenced by the site's

Synoptic Monitoring Program. Additional financial and

benthic community structure (particularly the amount

personnel support are needed to assist MBRS sites

of macroalgae and crustose coralline algae).

in monitoring this Level II component. Settlement-

plate data from the GEF Targeted Research program

Status

should soon become available. These data will greatly

enrich the overall understanding of settlement and

The average number of small (< 2 cm maximum

recruitment in the MAR.

diameter) recruits in the MAR averaged 3 recruits

per m2, with the highest value of 14 recruits per m2

Additional analysis is needed to understand patterns

observed at Long Caye, Lightouse Reef, Belize. The

of minimally viable recruitment levels, connectivity

MAR average is slightly lower than the Caribbean

patterns, and processes controlling recruitment

average (4.5 recruits per m2)9.

success in the MAR. Habitat-specific reference values

need to be developed, possibly for each subregion of

MAR fore reefs had slightly more average recruits (3

the MAR, based on an increased number of sampling

recruits per m2) than did reef crests (2 recruits per

sites and regional meta-analysis.

m2). Most coral recruits were brooding species, such

as agaricids. (Brooders produce planulae that settle

Virtually no data are available from settlement plate

relatively close to their "mother colonies.") Recruits of

studies in the MAR.

major reef-building corals were rare or absent9.