70 
Fishery Bulletin 115(1) 
Figure 7 
Distribution of oocyte diameters in (A) spawning capable and (B) ac- 
tively spawning female white anglerfish {Lophius piscatorius) collected 
from the northwestern Mediterranean Sea between June 2007 and De- 
cember 2010. 
yolk, which increases the potential for larval survival 
(Duarte and Alcaraz, 1989). The only information avail- 
able about egg diameters for other species of Lophius is 
for yellow goosefish, which occupy a bathymetric range 
that is similar to that occupied by white anglerfish and 
have a similar egg size (Yoneda et ah, 2001). In con- 
trast, the black anglerfish has an egg diameter of 1.88 
mm (SD 0.12), a size that is nearly 1.5 times smaller 
than the diameters reported for the white anglerfish 
and yellow goosefish, and inhabits shallower waters 
than those inhabited by the other 2 species (Colmenero 
et ah, 2015b). A comparative study of egg sizes in deep- 
sea species found that egg size increased significantly 
with depth (Fernandez-Arcaya®). Egg size is important 
to offspring survival in many organisms, and large 
eggs survive better than small ones in environments 
® Fernandez-Arcaya, U. 2015. Personal common. Departa- 
mento de Recursos Marinos Renovables, Institut de Ciencies 
del Mar, Passeig Man'tim de la Barceloneta, 37-49, 08003 
Barcelona, Spain. 
where dissolved oxygen is low (Hendry I 
and Day, 2003). 
r 
General remarks 
In this study, we estimated the spawning i 
season, size at sexual maturity, and fe- I 
cundity of white anglerfish. Considering 
the parameter values that we obtained, j 
we can conclude that this species is one ' 
that employs a K reproductive strategy. 
In general, this strategy is defined by a 
large body size, longevity, late matura- 
tion, and low fecundity (Pianka, 1970, 
1974). A wide range of deep-sea demersal 
fish species generally display life history 
characteristics consistent with if-selec- 
tion (Adams, 1980; Gage and Tyler, 1991). 
These traits make deep-sea fish stocks 
highly vulnerable to fishing and capable 
of little resilience to over-exploitation, 
increasing the urgency for the conserva- 
tion and management of this group of 
animals (Koslow et ah, 2000; Morato et ~ 
ah, 2006; Norse et ah, 2012). 
Theoretically, the /^-strategy for deep- 
sea fish species should imply a low fecun- 
dity; however, some species, such as the 
North Pacific armorhead iPseudopentace- 
ros wheeleri), wreckfish {Polyprion amer- 
icanus), and splendid alfonsino (Beryx 
splendens), have high fecundities (Sed- 
berry et ah, 1996; Lehodey et ah, 1997; 
Humphreys, 2000). White angelfish and 
species of Lophius in general also should 
be included in this group because of their 
high fecundity (Afonso-Dias and Hislop, 
1996; Colmenero et ah, 2013). This variability in re- 
productive strategy is the result of adaptation to envi- 
ronmental changes, such as temperature, bathymetric 
pressure, light, and food availability (Herring, 2002; 
Brown-Peterson et ah, 2011). Likely, the high fecundity 
and the low economic value of the white anglerfish, at 
least until the last decades of the 20th century, has 
allowed the stock to be sustainable within acceptable 
limits. With the recent expansion of anglerfish fisher- 
ies, sustainability is in question, and our study is the 
first step toward an informed assessment of this deep- j 
sea resource and its management with an ecosystem j 
perspective. 
Acknowledgments 
The authors would like to thank the crew of the fishing 
vessels Avi Pau, Estel-lada, Germans Felix, San Benito, 
and Port de Roses for allowing us to conduct sampling 
aboard their vessels. We also thank M. Baeta and L. 
