87 
National Marine 
Fisheries Service 
NOAA 
Fishery Bulletin 
o- established In 1881 -<r> 
Spencer F. Baird 
First U S Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Comparison of video and diver observations 
of sharks from a fishery-independent trap-video 
survey off east-central Florida, including utility of an 
alternative method of video analysis 
Email address for contact author: roldan.munoz@noaa.gov 
Abstract —We assessed the utility of 
an alternative method of video anal¬ 
ysis for generating data for sharks 
and compared observations of sharks 
from the use of baited remote under¬ 
water video stations (BRUVS) with 
observations made by scuba divers 
during surveys conducted simultane¬ 
ously with BRUVS video recordings. 
Videos were made off east-central 
Florida as part of a fishery-inde¬ 
pendent trap-video survey of fish 
species in hard-bottom reef habi¬ 
tats. In videos from 25 of 72 sites, 
we observed sharks, including the 
nurse ( Ginglymostoma cirratum), 
tiger ( Galeocerdo cuvier), spinner 
(Carcharhinus brevipinna), sandbar 
(C. plumbeus ), Atlantic sharpnose 
(Rhizoprionodon terraenovae), bull 
(C. leucas), and lemon ( Negaprion 
brevirostris) sharks. In contrast, div¬ 
ers observed 3 species of sharks at 5 
sites. We conclude that video obser¬ 
vations are superior to diver obser¬ 
vations for detecting sharks. Rapidly 
viewing an entire video (the alterna¬ 
tive method), rather than viewing 
only a 20-min segment (the stan¬ 
dard protocol), has the potential to 
increase the number of sites where 
sharks are observed and the number 
of shark species that are observed 
in video analysis (as it did, by 400% 
and 40%, respectively, in this study). 
This method holds promise for pro¬ 
viding critical information without 
extraction of specimens and for aid¬ 
ing stock assessments and essential 
fish habitat delineation for these im¬ 
portant predators. 
Manuscript submitted 24 August 2018. 
Manuscript accepted 12 April 2019. 
Fish. Bull. 117:87-96 (2019). 
Online publication date: 26 April 2019. 
doi: 10.7755/FB.117.1-2.10 
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. 
Roldan C. Munoz (contact author) 
Michael L. Burton 
Beaufort Laboratory 
Southeast Fisheries Science Center 
National Marine Fisheries Service, NOAA 
101 Pivers Island Road 
Beaufort, North Carolina 28516 
Predation is recognized as a key eco¬ 
logical and evolutionary process, and 
sharks, a group that includes species 
capable of being the top predators 
in oceans, are important members 
of marine communities (Estes et al., 
2011; Osgood and Baum, 2015; Bar¬ 
ley et al., 2017). Sharks are capable 
of exerting top-down effects on prey 
from lower trophic levels over wide 
spatial and temporal scales (Osgood 
and Baum, 2015; Barley et al., 2017; 
Dulvy et al., 2017), and shark species 
are valuable targets of recreational 
and commercial fisheries. To help 
protect species that have relatively 
low reproductive rates, late maturity, 
and slow growth, the United States 
has implemented shark management 
measures that are some of the stron¬ 
gest worldwide (NMFS 1 ). Despite 
conservation efforts, global bycatch 
of sharks and demand for shark fins 
and meat have resulted in -25% of 
shark species listed as endangered, 
vulnerable, or near threatened by 
the International Union for Con¬ 
1 NMFS (National Marine Fisheries Ser¬ 
vice). 2017. 2016 shark finning report 
to Congress, 117 p. [Available from 
website]. 
servation of Nature (IUCN) in the 
IUCN Red List of Threatened Spe¬ 
cies (Heithaus et al., 2010; Dulvy et 
al., 2014; White et al., 2015; Ward- 
Paige, 2017), although recent analy¬ 
ses indicate preliminary recovery of 
certain stocks of sharks in U.S. wa¬ 
ters of the Atlantic Ocean (Peterson 
et al., 2017). We lack even basic bio¬ 
logical information for many sharks 
and their relatives, such that 46% 
of species on the IUCN Red List are 
classified as data deficient (Heithaus 
et al., 2010; Dulvy et al., 2014; White 
et al., 2015; Peterson et al., 2017). 
Whereas fishery-independent sur¬ 
veys can provide valuable measures 
of relative abundance to inform stock 
assessments, one of the hindrances 
to accurate assessment of shark 
populations is the lack of fishery- 
independent surveys that are done 
on a stock-wide basis. The NOAA 
Northeast Fisheries Science Center 
conducts a biannual longline survey 
from the Gulf of Mexico to south¬ 
ern New England, and the NOAA 
Southeast Fisheries Science Center 
conducts an annual longline survey 
off the southeastern United States 
in the Atlantic Ocean and Gulf of 
Mexico. Although other fishery-in- 
