مورد إلكتروني
Comparison of two indexed gill-netting protocols for fish community surveys in Northern lakes
| العنوان: | Comparison of two indexed gill-netting protocols for fish community surveys in Northern lakes |
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| بيانات النشر: | Laurentian University of Sudbury 2017-01-18 |
| تفاصيل مُضافة: | Brekke, Lorraine J. |
| نوع الوثيقة: | Electronic Resource |
| مستخلص: | 1) I compared the performance of two standard fish community assessment protocols, the NORDIC protocol and the Broad-scale Fish Community Monitoring (BsM) protocol (the latter consisting of two gear types). I utilized fish catch and attribute data collected from 21 Boreal Shield lakes (17 in Ontario, 4 in NWT) surveyed using both protocols, in a pairwise design. Fish community composition (species richness, diversity, and evenness), relative abundance (number and biomass per 100 m of net), and body size distributions were compared between NORDIC and BsM surveys, and among the three gill net gears - NORDIC (NRD), North American Standard (NA1), and Ontario Small Mesh Standard (ON2). The NORDIC protocol dedicates a higher proportion of total sampling effort to small-mesh gear compared to the BsM protocol, and the ranking of gears according to proportion of small mesh effort is ON2 > NRD > NA1. NORDIC surveys used 38% greater effort (total length of net deployed per area of lake) than BsM surveys over the 21 lakes examined. 2) Principal components analysis (PCA) of species relative abundances showed significant differences between surveys in community compositions, as well as a separation of communities between Ontario and NWT lakes. NORDIC surveys detected 19% more species per survey, with the additional species primarily belonging to smallbodied taxa (e.g., Cyprinidae, Gasterosteidae, Cottidae). Paired-comparisons of gears indicated that NA1 gangs (highest proportion of large mesh) yielded fewer species, lower diversity, and higher evenness at standardized levels of effort compared to NRD and ON2 gangs, but there were no significant differences between NRD and ON2 gangs. 3) NORDIC surveys tended to provide higher numeric catch per unit effort (NPUE) and lower biomass per unit effort (BPUE) estimates compared to BsM surveys for the whole community, but differences between surveys were stronger and more consistent for smallbodied species than large-bodied species. For m |
| مصطلحات الفهرس: | NORDIC protocol, Broad-scale Fish Community Monitoring (BsM) protocol, fish community, Ontario, NWT lakes, NPUE, BPUE, gill-netting protocols, NORDIC (NRD), North American Standard (NA1), Ontario Small Mesh Standard (ON2), Thesis |
| الإتاحة: | Open access content. Open access content |
| ملاحظة: | English |
| أرقام أخرى: | LU$ oai:zone.biblio.laurentian.ca:10219/2730 https://zone.biblio.laurentian.ca/handle/10219/2730 1303187671 |
| المصدر المساهم: | LAURENTIAN UNIV LIBR & ARCHS From OAIster®, provided by the OCLC Cooperative. |
| رقم الأكسشن: | edsoai.on1303187671 |
| قاعدة البيانات: | OAIster |
| الوصف غير متاح. |