Document ID: EPA-HQ-OW-2002-0049-0072
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2003-03-19T05:00Z

Executive
Summary
°
Seagrass
ecosystems
are
protected
under
the
federal
"
no­
net­
loss"
policy
for
wetlands
and
form
one
of
the
most
productive
plant
communities
on
the
planet,
performing
important
ecological
functions.

°
Seagrass
beds
have
been
recognized
as
a
valuable
resource
critical
to
the
health
and
function
of
coastal
waters.
Greater
awareness
and
public
education,
however
is
essential
for
conservation
of
this
resource.

°
Tremendous
losses
of
this
habitat
have
occurred
as
a
result
of
development
within
the
coastal
zone.
Disturbances
usually
kill
seagrasses
rapidly,
and
recovery
is
often
comparatively
slow.

°
Mitigation
to
compensate
for
destruction
of
existing
habitat
usually
follows
when
the
agent
of
loss
and
responsible
party
are
known.
Compensation
assumes
that
ecosystems
can
be
made
to
order
and,
in
essence,
trades
existing
functional
habitat
for
the
promise
of
replacement
habitat.

°
While
planting
seagrass
is
not
technically
complex,
there
is
no
easy
way
to
meet
the
goal
of
maintaining
or
increasing
seagrass
acreage.
Rather,
the
entire
process
of
planning,
planting
and
monitoring
requires
attention
to
detail
and
does
not
lend
itself
to
oversimplification.

ix
°
The
success
rate
of
permit­
linked
mitigation
projects
remains
low
overall,
but
this
appears
to
result
from
failures
in
the
planning
process
as
much
as
any
other
cause.
To
prevent
continued
loss
of
habitat
under
compensatory
mitigation,
decisive
action
must
be
taken
by
placing
emphasis
on
improving
site
selection,
compliance,
generating
desired
acreage,
and
maintaining
a
true
baseline.

°
Seagrass
planting
is
no
longer
experimental,
but
planting
will
not
succeed
unless
managers
appreciate
and
emphasize
the
extreme
importance
of
site
selection,
care
in
planting,
and
incorporation
of
plant
demography
into
the
planning
and
planting
processes.

°
Seagrass
beds
can
be
restored,
but
preservation
is
the
most
cost­
effective
course
of
action
to
sustain
seagrass
resources.
Although
techniques
and
protocols
exist
that
produce
persistent
seagrass
beds,
they
are
often
applied
inconsistently,
which
has
resulted
in
large­
scale
failures.

°
A
logical
and
ecologically
defensible
goal
is
to
attain
replacement
of
the
lost
seagrass
species
with
an
area
of
bottom
coverage
that
compensates
for
interim
lost
resource
services
and
a
comparable
shoot
density.
Seagrass
plantings
that
persist
and
generate
the
target
acreage
have
been
shown
to
quickly
provide
many
of
the
functional
attributes
of
natural
beds.

°
When
destruction
of
the
impact
site
requires
planting
in
another
location
(
i.
e.,
offsite
it
is
often
difficult
to
find
a
site
elsewhere
with
suitable
biological
and
physical
parameters
required
for
seagrass
growth
and
persistence.

°
As
more
information
is
made
available
to
managers
regarding
the
function
of
seagrass
ecosystems
and
the
difficulties
involved
in
mitigating
for
their
loss,
fewer
permitted
impacts
are
occurring
with
more
emphasis
placed
on
impact
avoidance
and
minimization.
x
°
Guidelines
for
the
Conservation
and
Restoration
of
Seagrasses