1. Commercial Hagfish Traps: Proposed Minimum Hole Diameter
Photo Credit:
College of Charleston
Good morning President Sutton and Commission Members. My name is Kathryn Crane; I’m an environmental scientist with the Marine Region’s state managed fisheries program. I am here today to present our proposed regulatory change, which entails setting a minimum hole diameter for traps in the commercial hagfish fishery.
Fish and Game Commission Meeting June 4, 2014 Kathryn E. Crane Marine Region

2. Presentation Overview
Fishery background
Current regulations
Department trap study
Proposed regulation
In this presentation, I will begin by providing a brief overview of hagfish biology as well as the commercial hagfish fishery in California. Next, I’ll review the current regulations and the gear used by the industry. I’ll also review a recent Department-led study that examined the effects of trap hole diameter on hagfish catch characteristics and use the results from this study to support our proposed regulation.

3. Pacific Hagfish (Eptatretus stoutii) Ecologically important
Relatively low productivity
I would like to provide a brief introduction to the Pacific hagfish, which I will simply refer to as hagfish for the rest of this presentation. Although hagfish may not be the most charismatic marine fish species, they serve an important ecosystem function as scavenger animals and as sources of food. Due to the great depths at which they live (between 60 and 400 meters), they have been historically difficult to research. What we do know about them relevant to fisheries management suggests that they are slow-growing, long-lived fishes that produce relatively few eggs.
Photo Credit: University of Guelph
Photo Credit: NOAA Fisheries

4. Commercial Fishery in CA
Millions of Pounds
This figure outlines the history of the commercial fishery in California, represented by millions of pounds in statewide annual landings. In 1988, an unprecedented commercial fishery emerged which targeted hagfish for their skins. The fish were primarily exported to South Korea, where their skin was used to manufacture what is marketed as “eelskin” leather. Landings peaked in 1990 at five million pounds. For presumably market-based reasons, landings rapidly declined and the industry virtually disappeared until around At this point in time, it began to re-emerge as a 100% export food-fish fishery, with exports again being shipped primarily to South Korea. Landings since 2007 have remained relatively stable, fluctuating between roughly one and two million pounds annually.

5. Summary of Current Regulations
General trap permit required
Destruct device required
May only fish for hagfish
200 bucket traps or 500 Korean-style traps
There are few regulations that apply to the hagfish fishery. Fishermen are required to possess a general trap permit, which requires a destruct device to be present on each trap, and they may not combine hagfish trips with any other trip type. Regulations also limit the number and type of trap to a maximum of 200 bucket traps or 500 Korean-style traps. The photo to the right shows the two allowed trap types. This is one of the few remaining open access fisheries in California. There is no closed season, no minimum fish size, and no recreational fishery. In 2013, 20 boats participated in the fishery across the state.
Photo Credit: T. Tanaka, CDFW

6. The Bucket Trap Industry preferred method in California
Hagfish enter through funnel or “cone” on lid
Small hagfish escape through trap holes
Of the two allowed traps, bucket traps are the preferred method used by the industry. Each trap contains an entrance cone on the lid and many holes over the trap that allow small hagfish to escape, as you can see in the photo. By limiting the size of hagfish that can pass through the holes, the bucket hole diameter has a large influence over catch characteristics. Currently, the diameter of these holes is not regulated and the industry uses a range of sizes.
Photo Credit: CDFW file photo

7. Effect of Hole Diameter on Catch Characteristics
Department-fisherman collaborative study
Tested hagfish traps with four hole diameters
Evaluated effects on:
Catch volume
Average size (market quality)
Immature fish retention
In a recent Department-led study funded by Collaborative Fisheries Research West, staff worked with a commercial trap fishermen to evaluate the effects of hole diameter on catch characteristics. The study tested traps with four different hole diameters that were or are presently used in the fishery, using a standardized sampling design offshore of Moss Landing. Department staff documented the effects of hole diameter on total catch volume, take of immature-size hagfish, and average fish size in the catch. Average fish size was determined by the number of hagfish per pound in the catch, since live hagfish are virtually impossible to measure individually. A smaller number per pound indicates a larger average size. This metric is used by the industry to determine market quality, and in Department monitoring efforts.
CDFW file photo

8. Hole Size Study Results
(%)
100
(#/lb) 3
(lbs)
656
This graph summarizes the primary effects of hole diameter on catch characteristics. Across the bottom of the graph, we have the four hole diameters tested from the smallest on the left, to the largest on the right. I would like to take a minute to walk you through the three main results represented by the lines on the graph.
First, I would like to point out that overall catch volume is represented by the red line with large dashes. As hole diameter becomes larger, catch volume clearly decreases – particularly with holes larger than ½ inch.
The solid blue line represents the average size of fish in the catch, and very clearly increases as hole diameter becomes larger. This also means that market quality is higher for the industry at larger hole diameters.
The green line with small dashes represents the percentage of reproductively mature-sized females in the catch. As hole diameter becomes larger, we see that the catch is comprised of more reproductively mature-sized female fish. What this means is that immature fish – those that have not yet had the chance to reproduce- are being excluded from the catch at larger hole sizes. From a fisheries conservation perspective, this is desirable goal. As you can see on the figure, the majority of immature fish are excluded at 9/16 inch and 100% of immature fish are excluded at 5/8 inch hole diameter.
Ultimately, these results show a very clear tradeoff between catch volume and reduction in the take of immature fish as trap hole diameter increases, with 9/16 inch representing the intersection of these effects. 82
4.7
207

9. Proposed Regulation
Department recommends a minimum hole diameter of 9/16 inch for any trap used in the fishery
9/16 inch provides conservation benefit without significant economic impact
Serves as a precautionary measure
In light of those results, the Department recommends setting a minimum hole diameter of 9/16 inch for any trap used in the hagfish fishery. Reducing the take of immature fish is an important conservation measure, yet the Department recognizes the economic needs of the industry in terms of catch volume. We feel that recommending a minimum hole diameter of 9/16 inch would help promote sustainability of the fishery by reducing the take of reproductively immature fish, while maintaining economically viable fishery yields. Due to market demand for larger hagfish, the majority of commercial fishermen currently use 9/16 inch holes or larger, either voluntarily or as a requirement of their buyer. This regulation would serve as a precautionary measure that would help protect the reproductively immature portion of the population should the market lower its’ size standards in the future.

10. Environmental Scientist
Questions  Thank You
Kathryn E. Crane
Environmental Scientist 
Travis H. Tanaka
Thank you all for your time. I am available to answer any questions you may have, and I’ve also included the contact information of my colleague, Travis Tanaka, who was the principal investigator of the trap study and has authored the initial statement of reasons accompanying this presentation.
CDFW file photo

12. Hole Diameter
#/Pound
Catch (Pounds)
Mature-Size Females (%)
3/8 in.
4.7
656.5
82.5
1/2 in.
4.2
590.7
84.1
9/16 in.
3.5
399.2
94.6
5/8 in.
3.0
207.3
100.0

13. Add §180.6
Title 14, California Code of Regulations