304 
Fishery Bulletin 114(3) 
Figure 1 
Location of Point Heyer Artificial Reef in central Puget Sound, Washington, 
where 2 rockfish species (brown rockfish [Sebastes auriculatus] and copper 
rockfish [S. caurinus]) were monitored over a 7-year period to determine sea- 
sonal changes in abundance and to find evidence of seasonal migrations. 
Rankin, 2011; Hanan and Curry, 2012; Rankin et.al., 
2013), long-term trends in seasonal abundance have 
not been specifically addressed, and drawing informed 
conclusions from these studies about potential seasonal 
changes in abundance or movement patterns is ham- 
pered by the temporal or spatial scales over which they 
were conducted, numbers of fish tagged, or insufficient 
information (e.g., mark and recapture dates). Collective- 
ly, the studies indicate that most adults of both species 
maintain high site fidelity, although some exceptions 
have been observed; that habitat type (e.g., high-relief, 
low-relief, natural, artificial) may influence site fidelity 
and movement behavior; and that some level of homing 
ability from beyond their putative home range is likely. 
Estimates of home range for brown and copper rockfish 
vary widely, from <10 m^ over high relief habitat to 
4656 m^ over low relief habitat (Matthews 1990b; Tol- 
imieri et ah, 2009; Rankin et ah, 2013). 
The goal of our study was to determine whether 
there were patterned seasonal changes in abundance 
on the reef for either species, and if so, whether the 
observed patterns differed between species. In order 
to gain further insight into our monitoring results, we 
examined auxiliary data from a genetic study of brown 
Nakada, D. Rasmussen, N. Hall, K. Green, and S. McMil- 
lan. 2010. Baseline surveys of nearshore fishes in and near 
central California marine protected areas 2007-2009. Final 
project report submitted to the Ocean Protection Council, 
124 p. California Sea Grant College Program, La Jolla, 
CA. [Available at website.] 
rockfish that was conducted concurrently at our study 
site. These data, along with our findings, are discussed 
in the context of providing compelling evidence of rock- 
fish migratory behavior. Migrations are well known for 
many temperate-water marine fishes (e.g., cods, her- 
rings, and sharks) and are often associated with chang- 
es in seasonally variable resources, such as food sup- 
ply or shelter, or with spawning or mating behaviors 
(Harden Jones, 1968; McCleave et al., 1984; McKeown, 
1984; Smith, 1985). 
Materials and methods 
Point Heyer Artificial Reef (PHAR) is a high-relief, in- 
sular reef located along the eastern shore of Vashon 
Island in the hydrographically defined “main basin” 
(Ebbesmeyer et al. 1984) of central Puget Sound (Fig. 
1). Puget Sound is a glacially formed saltwater estu- 
ary Qord characterized by mixed semidiurnal tides. 
It is connected to the Pacific Ocean through one, ap- 
proximately east-west running strait (Strait of Juan de 
Fuca) that is bounded to the north by Canada’s Van- 
couver Island, and by a north-south running inland 
waterway between Vancouver Island and the Canadian 
mainland. It consists of 5 sub-basins that are sepa- 
rated by shallow-water sills. The bathymetry of Puget 
Sound extends to depths of nearly 300 m (all depths 
reported herein are corrected to mean lower low water 
depths). 
