During the fall of 2009 the New Jersey Division of Fish and Wildlife's Bureau of Marine Fisheries had the opportunity to collect striped bass biological samples on the party boat F/V Queen Mary based in Point Pleasant, NJ and during several fishing tournaments throughout the state. These types of sampling, in addition to the Division's field surveys, are valuable components of New Jersey's striped bass research and the coastwide assessment of the striped bass resource. PARTY BOAT SAMPLING For the sixth year since 1999, Captain John "JB" Brackett welcomed Division staff on the F/V Queen Mary to sample the striped bass catch. During this time, 753 fish were measured averaging 25.4 inches in total length (see Sampling Summary Table and Length Frequency Figure). Scale samples were collected from 663 fish for age determination, ranging from 2 to 13 years (see Age Frequency Data).

Click to enlarge

During two trips in the fall of 2009, 159 fish were measured averaging 27 inches, which was the highest mean length to date. Scale samples were collected from 116 striped bass to determine the age of the fish. Using methods described below, most fish caught on the Queen Mary were age 6 followed by age 5 (Age/Length Key pdf, 36kb). These ages were consistent with previous years where the majority of fish ranged from 4 to 6 years old. Six-year-old fish were from the 2003 year class which coincided with the highest index of New Jersey's Striped Bass Recruitment Survey. The survey has been conducted annually in the Delaware River since 1980 to develop an estimate of relative abundance for striped bass young-of-year. Refer to the article New Jersey's Priceless Resource - Studying the Delaware River on the Division's website for more detailed information about the seine survey.

Age Determination

Scales are the most common structure used to age striped bass primarily due to the ease of collection without harming the fish. Processing begins with sorting through the scales and placing the best samples on a rectangular piece of acetate (Scales image, top). The acetate is then placed between two thin metal plates and inserted in a heated hydraulic press. Once removed from the press, the scales are removed from the acetate leaving an impression (Scales image, bottom). The slide is then placed in a microfiche reader to determine the age. Using scales to age fish is similar to counting rings on a tree. Click for Scale (age 5) with arrows (pdf, 33kb) pointing to each "ring" or annuli.

Although scales are a reliable source of age determination, otoliths (small ear bones located inside the head) are proven to be more accurate especially as age increases. One disadvantage to using otoliths is that the fish must be sacrificed. Two otoliths are extracted from each fish head by removing the bones with tweezers. Once the otoliths are removed they are cleaned and placed in envelopes for processing at the lab. A low speed isomet saw is used to cut a thin slice through the core of the otolith. The cross section is mounted to a slide and viewed with a microscope to determine the age. Like scales, the process involves counting rings. Click to view a processed otolith ready to be aged (taken from Old Dominion University's striped bass ageing protocol by Christina Morgan and Hank Liao).

Tagging

Ageing with otoliths is not an option during tagging projects or situations where fish are released alive. From 1999 to 2001, scales were collected from 80 fish that were tagged and released aboard the Queen Mary (Tagging Summary Table). Unfortunately, it was determined that tagging was not practical during party boat trips and the numbers tagged were too low to conduct adequate analysis. Eleven of the tagged fish were recaptured generating an overall recapture rate of 14%. Time at large averaged 2.8 years and ranged from 158 days to 5.5 years (Tag Recapture Table). Ironically enough, the fish at large the longest was recaptured in Raritan Bay, not far from where it was tagged over five years before.

Anglers of all ages target striped bass. Click to enlarge

Recapture locations ranged from Massachusetts to North Carolina with the majority caught in New York, which was consistent with results from New Jersey's other tagging surveys. Refer to the article "Where Has My Fish Traveled?" (pdf, 320kb) on the Division's website for more detailed information about striped bass tagging. Please note that Figure 3 in that article is not correct. The length axis labels should read 0-50 in 5 inch increments at each line rather than 0-30 with 5 inch increments at every other line. Currently, striped bass age samples are collected primarily during the Division's Delaware Bay Tagging and Ocean Trawl Surveys. The majority of samples collected are scales from fish less than 30 inches caught in the spring. Party boat sampling is an excellent way to enhance survey data with much needed samples from the fall of both kept and released fish. Thanks again to JB and his crew for their continued cooperation.

TOURNAMENT SAMPLING

In addition to sampling aboard the Queen Mary, the Division attended several striped bass tournaments in the fall of 2009. Length and weight were collected from a total of 120 harvested striped bass, averaging nearly 38 inches and 21.5 pounds (Tournament Length Frequency Data). Scales were taken from all striped bass and a subsample of heads were collected from larger fish for otolith extraction at the lab. Using methods described above in the Age Determination section, fish sampled in 2009 ranged from 5 to 15 years with the majority aged at 13 years (Tournament Age Frequency Figure). Age 13 fish were from the 1996 year class which was an above average index from New Jersey's Striped Bass Recruitment Survey and the highest index for Maryland's similar survey on the Chesapeake Bay.

Seashell Striped Bass Derby
This was the third year the Division attended the annual Striped Bass Derby at the Seashell in Beach Haven, NJ. Samples were collected from the 80 fish caught during this two-day tournament. Mean length and weight were both larger than previous years, averaging 37.9 inches and 20.9 pounds (Seashell Tournament Summary Table). The overall size range of the fish was also larger in 2009 with the winning fish measuring 45 inches and 40 pounds. Comparable to other years, the catch was predominately female. Most fish caught during the 2009 tournament were aged at 11 and 13 years. Averaging 10.2 years, the ages were generally older than previous years due to increased numbers of larger fish caught.

South Jersey Big Bass Open
Eleven fish were sampled during the South Jersey Big Bass Open held at South Jersey Marina in Cape May, NJ. The fish averaged 38.5 inches and 23.1 pounds. The majority of fish were aged at 8 and 11 years old.

Bay Point Marina Striper Tournament
The Bay Point Marina Striper Tournament in Cedarville, NJ was another tournament attended by the Division in 2009. Samples were collected during the last day of the two-day tournament from 26 fish, averaging 38.1 inches and 25.7 pounds. The majority (20.5%) of the fish sampled were age 13.

Like party boat sampling, tournaments are beneficial in supplementing data to the Division's field surveys especially due to the ability for otolith collection. Since fish entered in tournaments are all harvested and are mostly larger fish, it is the preferred sampling method for collecting otoliths.