Double-crested cormorant distribution on catfish aquaculture in the Yazoo River Basin of Mississippi (original) (raw)
Related papers
2012
The Yazoo River Basin of Mississippi, USA, supports the largest concentration of hectares devoted to channel catfish, Ictalurus punctatus, aquaculture production in North America. The Yazoo Basin also supports large numbers of resident, wintering and migrating fish-eating birds, with the Doublecrested Cormorant, Phalacrocorax auritus, implicated as the most serious depredating species. We used data from aerial surveys of numbers and distribution of cormorants in the Yazoo Basin and on commercial catfish ponds during winters (November–April) 2000–2001 and 2003–2004 to refine estimates of regional economic losses due to cormorant depredation. In both periods, the greatest monthly estimates of cormorant foraging occurred from 1 January to 31 March. Losses in terms of biomass, number, and dollar value were greater for foodfish ponds than fingerling ponds. Monthly weighted estimates of catfish consumed were 1775.3 and 1346.6 m.t. over winters 2000–2001 and 2003–2004, respectively. Total ...
Journal of the World Aquaculture Society, 2012
The Yazoo River Basin of Mississippi, USA, supports the largest concentration of hectares devoted to channel catfish, Ictalurus punctatus, aquaculture production in North America. The Yazoo Basin also supports large numbers of resident, wintering and migrating fish-eating birds, with the Doublecrested Cormorant, Phalacrocorax auritus, implicated as the most serious depredating species. We used data from aerial surveys of numbers and distribution of cormorants in the Yazoo Basin and on commercial catfish ponds during winters (November-April) 2000-2001 and 2003-2004 to refine estimates of regional economic losses due to cormorant depredation. In both periods, the greatest monthly estimates of cormorant foraging occurred from 1 January to 31 March. Losses in terms of biomass, number, and dollar value were greater for foodfish ponds than fingerling ponds. Monthly weighted estimates of catfish consumed were 1775.3 and 1346.6 m.t. over winters 2000-2001 and 2003-2004, respectively. Total estimated losses for foodfish and fingerling ponds in 2000-2001 were 11.56and11.56 and 11.56and0.48 million, respectively, and in 2003-2004 were 5.22and5.22 and 5.22and0.40 million, respectively. Maximum dollar loss occurred during
Modeling the economic impacts of double-crested cormorant damage to a recreational fishery
The double-crested cormorant (Phalacrocorax auritus) has undergone a significant range expansion in the Great Lakes area of the United States since the 1970s, negatively impacting native fish populations and sport fisheries. Effective management of wildlife requires policies and practices that quantify their economic impacts, which is often complicated by multiplier effects in the regional economy. This analysis estimates the potential direct and regional economic impacts of the cormorant to a recreational fishery. We estimated that the potential economic loss was on average 5millionto5 million to 5millionto66 million annually, as well as 66 to 929 job-years in the region annually over a 20-year period (1990 to 2009). This approach to calculating the economic impacts of wildlife damage can be applied to other wildlife to provide the most accurate estimate of total economic impacts.
The economic impact of wildlife-caused damage and associated management is one of the many factors that arguably play a role in the decision-making process of wildlife managers. Often the role of an economist is to value the damage created by wildlife, or to assess programmatic efficiency to determine if changes can be made to increase return per dollar invested in management efforts. Frequently, the results of economic analyses of wildlife-caused damage are used to justify program efforts in the pursuit or maintenance of funding. The complexity of determining the economic impact of wildlife-caused damage requires that there is a clear understanding of the methodological approach used to determine impacts. Examining specific methodological approaches used in actual case studies provides a systematic replicable approach to valuing damage. This study outlines the methodology for determining the economic impact of cormorant damage to natural resources in a local economy: the Oneida Lak...
Principal economic effects of cormorant predation on catfish farms
Journal of the World Aquaculture Society, 2020
Substantial economic losses of farmed catfish to fish-eating birds such as the double-crested cormorant, Phalacrocorax auritus, continue to be reported on U.S. catfish farms. An economic analysis was conducted of the on-farm effects of both the increased expenditures to scare fish-eating birds from catfish farms and of the value of the catfish that were consumed by cormorants. A survey was conducted of U.S. catfish farmers in the Delta region of Mississippi and Arkansas, to obtain farm-level data on expenditures to scare birds. Estimations of the lost revenue from catfish consumed by cormorants were developed from a concurrent study on cormorant distribution, abundance, and diet in the region. The economic effects of bird predation in terms of both fish consumption and management costs were evaluated across three farm sizes and nine catfish production practices. Catfish farmers spent on average 704/ha±704/ha ± 704/ha±394/ha to scare birds, making bird-scaring costs one of the top five costs of raising catfish. The greatest cost components of scaring birds were manpower (39% of all birdscaring costs) and the variable and fixed costs of trucks used to scare birds (34% of all bird-scaring costs). Losses were greater on hybrid than channel catfish fingerling ponds.
The Economic Impact of the Catfish, Ictalurus punctatus, Industry on Chicot County, Arkansas
Journal of Applied Aquaculture, 2004
This study analyzed the contribution of the catfish industry to the economy of Chicot County, Arkansas, using an input-output model. The objective was to quantify the economic contribution of the industry in terms of creating new dollars, jobs, and income to the local community. Mail surveys and personal interviews were used to collect data from catfish farmers, processors and other businesses related to the catfish industry. For farmers, the information solicited included production and marketing costs, sales and employment. Out of approximately 85 questionnaires administered to catfish farms, 44 usable questionnaires were obtained for a response rate of 52%. Businesses directly related to the catfish industry provided information on employment and sales and included: processors, seiners and haulers, pond builders, tractor and equipment dealers, and feed bin manufacturers. Other businesses with indirect ties to the catfish industry included: input supply companies, banks, fertilizer and chemical companies, auto shops, electricians, and bookkeeping firms. The survey data were used to modify the IMPLAN database for Chicot County to reflect the 2001 level of catfish production, processing and services available to support the industry. This database was then used to estimate the economic impact of the industry to the county's economy. In 2001, the 85 catfish farmers in the Please note that this electronic prepublication galley may contain typographical errors and may be missing artwork, such as charts, photographs, etc. Pagination in this version will differ from the published version.
The Economics of Intensifying Catfish Production: A Production Function Analysis
Journal of the World Aquaculture Society, 1990
Yields of channel catfish in the United States have increased 89 a result of higher levels of stocking, feeding and aeration. A Cobb-Douglas production function wns estimated using survey data from 66 cat6sb ponds in West-Centrd Alabama to determine if further intensification of catfish production in West-Central Alabama would be profitable.
Economic Impact of a Recreational Striped Bass Fishery
North American Journal of Fisheries Management, 2014
Morone saxatilis are stocked in numerous southeastern U.S. reservoirs to enhance angling opportunities. Many of these reservoirs are near rural communities, where expenditures by anglers provide economic benefits. This study estimated the value of the recreational Striped Bass fishery at Lewis Smith Lake, Alabama, to the local counties surrounding the lake and the state of Alabama using surveys that collected information on angler expenditures; further, we calculated generated tax revenues and estimated the demand and consumer surplus for the fishery. Annual Striped Bass angler effort represented 23% of the total effort with 53,000 h (SE, 3,800 h) or approximately 10,200 trips. Catch and harvest effort for Striped Bass anglers was 0.40 fish/h and 0.18 fish/h, respectively. Annual aggregated expenditures by Striped Bass anglers were US$0.7 million, with 84% of expenditures occurring within the local counties. A cost-benefit analysis determined that for every 1spentinstockingcosts,1 spent in stocking costs, 1spentinstockingcosts,2 were generated in taxes for local county road maintenance, education, and general funds and 7weregeneratedforstatewidetax−fundedprograms;thus,StripedBassstockingcostswerejustifiedthroughtheincreaseinresultinganglerexpenditures.Acountmodelusinganegativebinomialdistributionwasusedtoestimatedemand.DemandestimationshowedthatanincreaseintravelcosttothesiteandanincreaseinpartysizedecreasedthenumberofvisitsananglerwouldmaketofishforStripedBassatLewisSmithLake.Consumersurpluswasestimatedtobe7 were generated for statewide tax-funded programs; thus, Striped Bass stocking costs were justified through the increase in resulting angler expenditures. A count model using a negative binomial distribution was used to estimate demand. Demand estimation showed that an increase in travel cost to the site and an increase in party size decreased the number of visits an angler would make to fish for Striped Bass at Lewis Smith Lake. Consumer surplus was estimated to be 7weregeneratedforstatewidetax−fundedprograms;thus,StripedBassstockingcostswerejustifiedthroughtheincreaseinresultinganglerexpenditures.Acountmodelusinganegativebinomialdistributionwasusedtoestimatedemand.DemandestimationshowedthatanincreaseintravelcosttothesiteandanincreaseinpartysizedecreasedthenumberofvisitsananglerwouldmaketofishforStripedBassatLewisSmithLake.Consumersurpluswasestimatedtobe0.6 million for the Striped Bass fishery and $77 per angler visit. In conclusion, this work has shown that the economic impact assessment for a fishery should be taken into account when total fishery management plans are being evaluated.
A model for evaluating interventions designed to reduce post-harvest fish losses
Fisheries Research, 1998
A general compartmentalised model which follows the fate of fish entering and leaving discrete stages between capture and sale at retail markets and the consequent changes in potential revenues at different stages is presented. The model can be used as a first step for evaluating the economic effects of different interventions designed to minimise post-harvest losses and was designed to be capable of expansion, to include progressively more complex situations, or to be contracted for adaptation to specific fishery systems and so become a useful tool for policy-makers and fisheries officers. The potential usefulness of the model is described using an example of an abridged version. This compares the results of transporting Nile Ž . Perch Lates niloticus caught in three different ways at Lake Victoria, Tanzania, and transported either by rail or by air to markets in Dar-es-Salaam, in a sequential chain with the highest losses occurring at the processing stage. It is concluded that to catch fish in beach seine nets and to transport them by air results in the best monetary return amongst the six comparisons made. q