Aldo S. Steffe

Supplemented Access Point Sampling Designs: A Cost-Effective Way of Improving the Accuracy and Precision of Fishing Effort and Harvest Estimates Derived from Recreational Fishing Surveys

Abstract We describe a cost-effective method for improving the accuracy and precision of fishing effort and harvest estimates derived from recreational fishing surveys that include an access point method for effort estimation (e.g., traditional access point surveys and bus route designs). Validated auxiliary data that quantify recreational fishing effort at access points within the fishery are used to supplement an existing access point design. This supplemented access point survey (SAPS) method is a form of double sampling and should be viewed as an extension of an access point design. Case study data from a boat-based estuarine fishery in Australia have been used to demonstrate changes in the relative accuracy and precision between a traditional access point design and the supplemented design. We found that the traditional design provided annual effort and harvest estimates for dusky flathead Platycephalus fuscus that were about 7% and 5% lower, respectively, than those obtained with the supplemented de...

Scale- and context-dependent selection of recreational harvest estimation methods: the Australasian experience.

Abstract Fisheries managers are becoming increasingly aware of the need to quantify all forms of harvest, including that by recreational fishers. This need has been driven by both a growing recognition of the potential impact that noncommercial fishers can have on exploited resources and the requirement to allocate catch limits between different sectors of the wider fishing community in many jurisdictions. Marine recreational fishers are rarely required to report any of their activity, and some form of survey technique is usually required to estimate levels of recreational catch and effort. In this review, we describe and discuss studies that have attempted to estimate the nature and extent of recreational harvests of marine fishes in New Zealand and Australia over the past 20 years. We compare studies by method to show how circumstances dictate their application and to highlight recent developments that other researchers may find of use. Although there has been some convergence of approach, we suggest th...

Recreational Fishing Effort, Catch, and Harvest for Murray Cod and Golden Perch in the Murrumbidgee River, Australia

AbstractRecreational fishery management aims to prevent species decline and provide sustainable fisheries. Overfishing has been frequently suggested as a cause of historic fishery declines within the Murray–Darling Basin (MDB), Australia, but there have been few quantitative surveys for providing fishery-dependent data to gauge status. The Murray Cod Maccullochella peelii and the Golden Perch Macquaria ambigua are important species targeted by recreational fishers across the MDB. The fisheries are controlled by size and bag limits and gear restrictions (both species) as well as a closed season (Murray Cod only). A complemented fisher survey design was used to assess the recreational fishery for both species in a 76-km reach of the Murrumbidgee River in 2012–2013. Progressive counts were used to quantify boat- and shore-based fishing effort. Catch and harvest rate information was obtained from shore-based fishers via roving surveys and from boat-based fishers via bus route surveys. Murray Cod catch rates (...

The Importance of Validating the Duration of Fishing Trips: Are Harvest Rates from On-Site Recreational Fishing Surveys Unbiased?

Abstract Harvest rates are often used as indicators of fishing quality and in the estimation of total harvest in some on-site survey designs. The unbiased estimation of harvest and fishing effort is critical for calculating accurate harvest rates. On-site survey designs allow survey clerks to validate harvest data directly. This harvest validation assumes that the level of intentional deception by fishers is relatively small. Therefore, validating angler-generated estimates of trip duration is important because this can provide evidence that harvest rates and other variables derived from effort data are also unbiased. Also, one can partition effort and harvest within trips to calculate directed harvest rates for different target species or species groups, knowing that the angler-generated estimates of total trip length are not contributing systematically to any bias in the directed harvest rates. We examined the accuracy of trip duration estimates reported by trailer boat fishers in the marine waters of N...