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Fishery Bulletin 11 7(1—2) 
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1965 1975 1985 1995 
Year 
2005 
2015 
Figure 1 
Number of publications related to red snapper (Lutjanus campecha- 
nus ) reproductive biology from 1965 through 2017. Each bar repre¬ 
sents a 5-year bin, with the exception of 2015, which represents 3 
years. Figure includes all publications from the Gulf of Mexico and 
the Atlantic Ocean. 
lications on reproductive biology have in¬ 
creased to 2.16/year according to a search 
of the internet with Google Scholar (Fig. 
1). It is well documented that red snap¬ 
per have an extended spawning season 
in the GOM, generally ranging from May 
through October, and peak spawning oc¬ 
curs from June through mid-September 
(SEDAR 31, 2013). Female red snapper 
are batch spawners with indeterminate 
fecundity, and the spawning interval, 
or number of days between consecutive 
spawnings, decreases with increasing fe¬ 
male size or age (Porch et ah, 2015). Fe¬ 
male red snapper can reach sexual matu¬ 
rity as early as age-2 (SEDAR 31, 2013, 
Porch et al., 2015). 
The reproductive potential of female 
red snapper has been shown to vary with 
region, habitat, and time. Red snapper 
from the east coast of the United States 
were more fecund and had a shorter 
spawning interval than those from off 
the Dry Tortugas in the Gulf of Mexico, 
although spawning seasonality appeared 
similar in both areas (Brown-Peterson et 
al., 2009). Recent modeling of red snap¬ 
per biomass and fecundity has indicated 
that both estimates are higher for the 
northwestern GOM than for the north¬ 
eastern GOM (Porch et al., 2015, Karnauskas et al., 
2017). These reported differences are likely related 
to the higher proportion of larger, older individuals 
in the northwestern GOM than in the northeastern 
GOM (Porch et al., 2015). Reproductive potential has 
also been hypothesized to be related to habitat; fish 
captured on natural reef banks reproduce earlier, at a 
smaller size, more frequently, and with a higher fecun¬ 
dity than fish captured on artificial reefs in Louisiana 
(Glenn et al., 2017). However, small sample sizes and 
differences in depth between the natural reefs and ar¬ 
tificial reefs reported in Glenn et al. (2017) may con¬ 
found the conclusions from this article. For example, 
no difference was found in spawning behavior or fe¬ 
cundity of female red snapper captured from oil plat¬ 
forms or natural hard bottom in Texas within the same 
depth zone (Downey et al., 2018). However, female red 
snapper captured on nearshore artificial reefs in Texas 
exhibited more active spawning and higher fecundity 
than those taken from offshore artificial reefs (Alexan¬ 
der, 2015), despite similarities in depth between near¬ 
shore and offshore reefs. Finally, female red snapper 
showed a decrease in fecundity and spawning frequen¬ 
cy, as well as a slower progression to sexual maturity 
between 2000 and 2010, and these results were more 
pronounced in fish from the northwestern GOM than in 
the northeastern GOM (Kulaw et al., 2017). However, 
the conclusions of Kulaw et al. (2017) may have been 
influenced by small sample sizes during 2009-2010, 
particularly from the northeastern GOM. 
To further examine potential temporal and spatial 
changes in reproductive parameters of GOM female 
red snapper, we conducted an expanded meta-analysis 
of several reproductive parameters from 1991 through 
2017. This 27-year period represents a time during 
which red snapper stocks have increased from historic 
low levels despite undergoing relatively high levels of 
fishing pressure. Specifically, we evaluated differences 
in spawning seasonality, batch fecundity, and spawn¬ 
ing interval across time. Additionally, we modeled dif¬ 
ferences in spawning interval and batch fecundity be¬ 
tween eastern and western subgroups of red snapper in 
the northern GOM. 
Materials and methods 
Data sources 
We searched Google Scholar for “red snapper reproduc¬ 
tion” and “Lutjanus campechanus reproduction” and 
selected articles published between 1991 and 2018 
containing information on any of the following terms: 
spawning, spawning seasonality, fecundity, spawning 
interval/frequency, spawning behavior, and gonadal 
histology. Additional relevant papers not found in the 
search were included on the basis of those with expert 
knowledge. The relatively few articles published on red 
snapper reproduction before 1991 that contained us¬ 
able data resulted in large gaps in the time series of 
