Dataset: low-profile gillnet_substrate
Deployment: NEC-KK2004-1

The methodology appeared effective at sampling groundfish abundance and distribution in the CLCA, and could potentially be used for a longer term monitoring program for this area. Although recent studies in the CLCA are extremely limited, this study indicated that groundfish are still abundant on Cashes Ledge. In general, this study demonstrated abundance of white hake, cod, and pollock in this area. Sampling in the spring and summer was also enough to demonstrate that seasonal patterns exist in these species abundances in the closure area. White hake was the most abundant species sampled . Abundance differed substantially with location and time. Highest abundance was during late June and July at the two shallower sites (e.g., 115 white hake were sampled at the 50 fm site on 12 July). A large portion of the white hake during this time had external signs of spawning, indicating that this could be an important spawning area. Very few white hake were observed at the deepest station (C). Cod were most abundant at the 50 fm station in June, while abundance was still increasing at the 22 fm station in mid-August when the survey was completed. In general, variability in cod abundance was much lower than that of white hake. In the 1980s, juvenile cod were frequently observed in studies of the kelp forests of Cashes Ledge (Vadas and Steneck 1988, 1995; Witman and Sebens 1992). Video methods determined that the distribution and abundance of Cashes Ledge cod was approximately an order of magnitude higher than the densities on several inshore ledges (Witman and Sebens 1992). Steneck (1997) determined that the average cod size recorded on Cashes Ledge in the 1980's ranged between 30 and 40 cm (approximately 2 years old based on average growth curves for the Gulf of Maine and Georges Bank [Bigelow and Schroeder 1953]). Older cod are generally found in deeper water (Swain 1993), but Steneck (1997) recorded cod up to a meter in length within the kelp forest at 30 m on Cashes Ledge (i.e., Ammen Rock). Jigging while on station yielded a high catch rate of cod at and around the kelp forest, and cod up to 18 kg (40 lbs) were caught at that location. Pollock were captured by all four mesh sizes of gillnets deployed in the CLCA in 2005 (each net consisted of 4 attached panels with 5.5-, 6-, 6.5-, and 7-inch mesh). There were two distinct size groupings that ranged from 30-50 cm and 65-85 cm.Pollock were well-represented in all four mesh sizes. It would be appropriate based on these results to expand this work to a longer time period so that trends in abundance can be monitored year round and between years. It would also be appropriate for future studies to consider monitoring outside of the closure area to allow for analysis of any effects the closure may have on distribution and abundance of groundfish, particularly cod, pollock and white hake in the region.

The methodology appeared effective at sampling groundfish abundance and
distribution in the CLCA, and could potentially be used for a longer term monitoring
program for this area.
Although recent studies in the CLCA are extremely limited, this study indicated
that groundfish are still abundant on Cashes Ledge. In general, this study demonstrated
abundance of white hake, cod, and pollock in this area. Sampling in the spring
and summer was also enough to demonstrate that seasonal patterns exist in these species’
abundances in the closure area.
White hake was the most abundant species sampled .
Abundance differed substantially with location and time. Highest abundance
was during late June and July at the two shallower sites (e.g., 115 white hake were
sampled at the 50 fm site on 12 July). A large portion of the white hake during this time
had external signs of spawning, indicating that this could be an important spawning area.
Very few white hake were observed at the deepest station (C).
Cod were most abundant at the 50 fm station in June, while abundance was still
increasing at the 22 fm station in mid-August when the survey was completed. In general, variability in cod abundance was much lower than that of white hake.
In the 1980s, juvenile cod were frequently observed in studies of the kelp forests of
Cashes Ledge (Vadas and Steneck 1988, 1995; Witman and Sebens 1992). Video
methods determined that the distribution and abundance of Cashes Ledge cod was
approximately an order of magnitude higher than the densities on several inshore ledges
(Witman and Sebens 1992). Steneck (1997) determined that the average cod size
recorded on Cashes Ledge in the 1980’s ranged between 30 and 40 cm (approximately 2
years old based on average growth curves for the Gulf of Maine and Georges Bank
[Bigelow and Schroeder 1953]). Older cod are generally found in deeper water (Swain
1993), but Steneck (1997) recorded cod up to a meter in length within the kelp forest at
30 m on Cashes Ledge (i.e., Ammen Rock). Jigging while on station yielded a high catch
rate of cod at and around the kelp forest, and cod up to 18 kg (40 lbs) were caught at that
location.
Pollock were captured by all four mesh sizes of gillnets deployed in the CLCA in
2005 (each net consisted of 4 attached panels with 5.5-, 6-, 6.5-, and 7-inch mesh). There
were two distinct size groupings that ranged from 30-50 cm and 65-85 cm.Pollock were well-represented in all four mesh sizes.
It would be appropriate based on these results to expand this work to a longer time
period so that trends in abundance can be monitored year round and between years. It
would also be appropriate for future studies to consider monitoring outside of the closure
area to allow for analysis of any effects the closure may have on distribution and
abundance of groundfish, particularly cod, pollock and white hake in the region.