323 
National Marine 
Fisheries Service 
NOAA 
Fishery Bulletin 
Hr established in 1881 ■<?. 
Spencer F. Baird 
First U S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Reproduction, first-year growth, and expansion of 
spawning and nursery grounds of black sea bass 
{Centropristis striata) into a warming Gulf of Maine 
Email address for contact author: richard.mcbride@noaa.gov 
Abstract— -The black sea bass (Cen- 
tropristis striata ) is extending its 
range northward, into a warming 
Gulf of Maine. Here, we plot the geo¬ 
graphic distribution of specific life 
stages to examine whether spawning 
and settlement, and therefore pro¬ 
ductivity, are extending northward. 
In order to align these life stages 
with the correct sampling season, 
we first resolve confusion about the 
spawning seasonality of this species, 
by collecting age-0 individuals from 
coastal waters of southeastern Mas¬ 
sachusetts (Buzzards Bay and Nan¬ 
tucket Sound) and aging them by 
using daily otolith microincrements. 
Wild-caught age-0 fish (?i=381), 
ranged in size from 32 to 88 mm to¬ 
tal length (mean: 53 mm [standard 
deviation (SD) 11]), and in age from 
50 to 129 d old (84 d [SD 16]). They 
hatched from May 2 to July 21 (June 
6 [SD 14 d]), and grew at linear 
rates from 0.32 to 1.22 mm/d (0.65 
mm/d [SD 0.15]). The literature and 
two 40-year trawl surveys confirm 
that black sea bass have spawned in 
Buzzards Bay and Nantucket Sound 
since the 1880s. Farther north, in 
the southern Gulf of Maine, spawn¬ 
ing has likely occurred in the last 
15 years. Settlement has increased 
about 1°N latitude over the recent 4 
decades in association with warming 
sea temperatures in the southern 
Gulf of Maine. 
Manuscript submitted 30 March 2018. 
Manuscript accepted 29 August 2018. 
Fish. Bull. 116:323-336 (2018). 
Online publication date: 27 September 2018. 
doi: 10.7755/FB.116.3-4.10 
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. 
Richard S. McBride (contact author ) 1 
Matthew K. Tweedie 2 
Kenneth Oliveira 2 
1 Northeast Fisheries Science Center 
National Marine Fisheries Service, NOAA 
166 Water Street 
Woods Hole, Massachusetts 02543 
2 Department of Biology 
University of Massachusetts Dartmouth 
285 Old Westport Road 
North Dartmouth, Massachusetts 02747-2300. 
The black sea bass (Centropristis 
striata ) is an important fishery spe¬ 
cies in temperate and subtropical 
latitudes of the western North Atlan¬ 
tic Ocean (Musick and Mercer, 1977; 
Hood et ah, 1994; NEFSC 1 ) and is 
the only serranid that spawns north 
of Cape Hatteras, North Carolina 
(Kendall, 1972). The northernmost 
stock, subject of this study, has been 
historically distributed in temper¬ 
ate waters from Cape Hatteras to 
Cape Cod, Massachusetts (Roy et ah, 
2012; McCartney et al., 2013; Mc¬ 
Bride, 2014), but in recent years its 
range has been extending northward 
into the colder Gulf of Maine (Klein- 
MacPhee, 2002; Miller et al., 2016). 
Coastal warming along the U.S. 
northeast coast is accompanied by 
the shifting distributions for many 
marine species (Nye et al., 2009; Per¬ 
1 NEFSC (Northeast Fisheries Science 
Center). 2017. 62nd Northeast Re¬ 
gional Stock Assessment Workshop 
(62nd SAW) assessment summary re¬ 
port. Northeast Fish. Sci. Cent. Ref. 
Doc. 17-01, 37 p. [Available from web¬ 
site.] 
shing et al., 2015; Henderson et al., 
2017), and has led to predictions of 
“winning and losing” species as cli¬ 
mate changes (Graham and Harrod, 
2009; Hare et al., 2016). Unlike some 
New England species that appear 
to be losing ground in the region, 
the warm-temperate black sea bass 
may be a winner; however, our abil¬ 
ity to predict the effects of climate 
on fish remains difficult (Brander, 
2015; Kleisner et al., 2017; Frank 
et al., 2018). For example, it is un¬ 
clear whether random individuals or 
a specific subset of adults are simply 
moving farther north on a seasonal 
basis, or whether spawning or settle¬ 
ment is increasing in previously un¬ 
occupied or sparsely populated habi¬ 
tats of the Gulf of Maine. 
Fish movements may be a cause 
for distributional shifts. This north¬ 
ern stock is composed of subregional 
‘contingents’ that provide evidence 
of phenotypic, particularly meristic, 
variation along a latitudinal cline 
(Shepherd, 1991). A potential mech¬ 
anism underlying this phenotypic 
cline is contingent-specific seasonal 
