419 
NOAA 
National Marine 
Fisheries Service 
Abstract— The dolphinfish ( Cory - 
phaena hippurus) is of major rec- 
reational and commercial impor- 
tance, and landings have increased 
in recent years around Puerto Rico, 
throughout the Caribbean Sea, and 
along the U.S. East Coast, yet its 
genetic structure among these lo- 
calities is uncertain. A portion of the 
mitochondrial nicotinamide adenine 
dinucleotide (NADH) dehydrogenase 
subunit 1 (ND1; 1288 base pairs) 
gene was used at 2 spatial scales 
to investigate the population struc- 
ture of dolphinfish. In a comparison 
of 183 specimens of dolphinfish be- 
tween the northern and southern 
coasts of Puerto Rico over 4 consecu- 
tive years (2010-2013), no genetic 
differentiation was detected (<J>st = 
-0.002, P=0.640). On a broader 
scale, patterns of genetic variation 
of ND1 were compared for samples 
collected throughout the western 
central Atlantic from Florida, South 
Carolina, North Carolina (southeast- 
ern United States; N=9Q); Puerto 
Rico (northeastern Caribbean Sea; 
N= 183 ); Barbados, Dominica, and 
Trinidad and Tobago (eastern Ca- 
ribbean Sea; N=43); and the central 
North Atlantic in the Azores Islands 
(N=8), and 199 haplotypes were 
identified from all of the regions 
combined. Analysis of all samples 
(N=324) revealed shallow genetic 
structure (<J>gx=0.009, P= 0.023), but 
pairwise regional comparisons did 
not, indicating low population differ- 
entiation of dolphinfish throughout 
the western central Atlantic. 
Manuscript submitted 26 May 2014. 
Manuscript accepted 28 July 2015. 
Fish. Bull. 113:419-429 (2015). 
Online publication date: 14 August 2015. 
doi: 10.7755/FB. 113.4.5 
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. 
Fishery Bulletin 
fir established 1881 •<?. 
Spencer F. Baird 
First U.S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Genetic structure and dispersal capabilities 
of dolphinfish (Coryphaena hippurus ) in the 
western central Atlantic 
Wessley B. Merten (contact author ) 1 - 3 
Nikolaos V. Schizas 1 
Matthew T. Craig 2 
Richard S. Appeldoorn 1 
Donald L. Hammond 3 
Email address for contact author: wessleymerten@gmaii.com 
1 Department of Marine Sciences 
University of Puerto Rico, Mayaguez 
PO. Box 9000 
Mayaguez, Puerto Rico 00681 
2 Department of Marine Science and Environmental Studies 
University of San Diego 
5998 Alcala Park 
San Diego, California 92110 
3 Cooperative Science Services LLC 
Dolphinfish Research Program 
961 Anchor Road 
Charleston, South Carolina 29412 
The combination of tagging and 
genetic approaches (e.g., DNA se- 
quencing and microsatellite analy- 
ses) has led to significant improve- 
ments in characterizing the stock 
and population structure of marine 
pelagic fishes, in interpreting bio- 
mass dynamic models, in generat- 
ing stock-recruitment curves, and in 
conducting cohort analyses (Graves, 
1998; Reiss et ah, 2009). Specifi- 
cally, tag and genetic data can be 
used to estimate regional biomass 
exchange and define stocks demo- 
graphically; this information is use- 
ful in the stock assessment process 
(Waples et ah, 2008). Alternatively, 
tag or genetic data have allowed 
scientists to refine assessment mod- 
els and facilitate a more precise 
allocation of management effort. 
Therefore, this combination of ap- 
proaches provides more realistic es- 
timates of immigration, emigration, 
mortality (natural and anthropo- 
genic), and the extent of population 
mixing, all of which are informative 
in assessment models (Hilborn and 
Walters, 1992). 
The results of these models pro- 
vide fishery managers with informa- 
tion necessary to adjust fishing ef- 
fort, set size limits and quotas, iden- 
tify seasonal hot spots and essential 
fish habitat (e.g., Sargassum), and 
protect spawning stocks to safeguard 
recruitment and future landings (Al- 
lendorf et ah, 1987), although the ap- 
plicability of management measures 
can vary depending on effective pop- 
ulation size (i.e., small versus large). 
Nevertheless, tag and genetic data 
are increasingly used to manage 
highly migratory fish stocks because 
they provide better estimates of 
spatiotemporal population differen- 
tiation and effective population sizes 
(Hauser and Carvalho, 2008) 
