283 
Release mortality in the red snapper 
{Lutjanus campechanus ) fishery: 
a meta-analysis of 3 decades of research 
Email address for contact author: matthew.d.campbell@noaa.gov 
1 Mississippi Laboratories 
Southeast Fisheries Science Center 
National Marine Fisheries Service, NOAA 
3209 Frederic Street 
Pascagoula, Mississippi 39567-4112 
2 Fish and Wildlife Research Institute 
Florida Fish and Wildlife Conservation Commission 
100 Eighth Avenue SE 
Saint Petersburg, Florida 33701-5020 
3 Sustainable Fisheries Division 
Southeast Fisheries Science Center 
National Marine Fisheries Service, NOAA 
75 Virginia Beach Drive 
Miami, Florida 33149-1003 
Abstract— The value of catch-and-re- 
lease fishing as a conservation mea- 
sure is highly dependent upon rates 
of discard frequency and release 
mortality. Therefore, it is important 
to understand how estimates of 
these variables are affected by fac- 
tors such as capture depth and wa- 
ter temperature. The meta-analytical 
approach to modeling used here for 
red snapper ( Lutjanus campechanus ) 
in the Gulf of Mexico provides a ro- 
bust method for dealing with study- 
specific differences in experimental 
protocols and for estimating release 
(discard) mortality as a function of 
key factors. Results of this analysis 
showed significant increases in mor- 
tality by depth and for the commer- 
cial sector. The most consistent re- 
sult was the positive correlation be- 
tween depth and estimates of release 
mortality, a relationship that was 
present regardless of study method, 
fishing sector, hook type used, or 
season of study. The effect of venting 
(deflating the swim bladder by punc- 
ture) was dependent on whether the 
study produced estimates of immedi- 
ate or delayed mortality. Immediate 
estimates indicated that mortality 
rates are lowered by venting where- 
as delayed estimates indicated that 
venting increased mortality rates. 
This result is largely reflective of 
the use of submergence ability, from 
surface-release studies, as a proxy 
for mortality. The model’s interaction 
result indicates that recompression 
of fish may be a viable alternative 
to venting and that, if a recompres- 
sion device is not available, venting 
at least improves the likelihood that 
a fish can submerge and return to 
protective habitat. The depth-based 
functional relationships developed 
in this model were used in the most 
recent red snapper stock assessment 
in 2012, and that use was a change 
from previous assessments where 
region-specific point estimates were 
used. 
Manuscript submitted 5 June 2013. 
Manuscript accepted 4 August 2014. 
Fish. Bull. 112:283-296 (2014). 
doi:10.7755/FB. 112.4.5 
The views and opinions expressed or 
implied in this article are those of the 
author (or authors) and do not necessarily 
reflect the position of the National 
Marine Fisheries Service, NOAA. 
Matthew D. Campbell (contact author ) 1 
William B. Driggers III 1 
Beverly Sauls 2 
John F. Walter 3 
The use of catch-and-release (CAR) 
fishing as a conservation measure 
began in Great Britain during the 
19 th century, eventually was prac- 
ticed in the United States volun- 
tarily by the early 1900s, and was 
used first as a management tool 
in salmonid fisheries in the 1950s 
(Policansky, 2002). Since that time, 
it has been practiced successfully to 
promote sustainable fisheries and 
is widely accepted by many anglers 
as a wise conservation strategy. The 
intent behind CAR regulations is to 
reduce fishing mortality for impor- 
tant age groups of fish, often to al- 
low young ages to grow and mature 
to reproductive ages or to protect 
spawning adults. Catch-and-release 
requirements in the red snapper 
( Lutjanus campechanus) fishery have 
expanded in recent years to encom- 
pass the release of all size classes 
during seasonal (or longer) closures 
in response to fishery management 
plans required by the Magnuson-Ste- 
vens Fishery Conservation and Man- 
agement Act and which place strict 
limits on total removals, including 
those in open-access recreational 
fisheries. 
Despite the intent of CAR fishing 
regulations, for many species, stress 
from capture can lead to barotrauma 
injuries and reduced reflex responses 
that result in increased release mor- 
tality and render some CAR mea- 
sures ineffective (Campbell et al., 
2010a; Davis, 2010). Stressors expe- 
rienced by fish during CAR fishing 
can include hooking trauma, physi- 
cal overexertion, barotrauma, rapid 
thermal change, air exposure, and 
physical handling (Davis et al., 2001; 
Rummer and Bennett, 2005; Nieland 
et al., 2007; Jarvis and Lowe, 2008). 
These stressors from CAR fishing 
may also translate into long-term, 
sublethal, negative consequences, 
such as reduced growth and fecundi- 
ty (Woodley and Peterson, 2003; Ryer 
et al., 2004; Davis, 2007). The effects 
of CAR fishing can be problematic 
particularly for marine species like 
red snapper that inhabit relatively 
deep water and possess a physoclis- 
