Stable isotope analyses offer a useful means for quantifying ecological niche dimensions, though few studies have examined isotopic response of an community with respect to resource gradients such as fluctuations in prey availability. carbon and nitrogen isotopes were measured Lake Michigan salmonines their collected from 2014 2016. Bayesian ellipse mixing model used quantify characteristics di...

Abstract The anadromous alewife is a commercially fished clupeid in Atlantic Canada, whose oceanic migration poorly understood. Migration of alewives presently investigated from the lower reaches Gaspereau River into Minas Basin, Bay Fundy. Seventy-five post-spawning adults were tagged on their downstream migration; within two days being tagged, most had left and 57 entered Southern Bight Basin...

The Gulf of Maine, USA is home to four colonial co-nesting tern species: Least Tern (Sternula antillarum), Common (Sterna hirundo), Arctic paradisaea), and the federally endangered Roseate dougallii). Over three decades visual observations chick provisioning were compiled for a comparative dietary study in region, including first detailed descriptions diets. Three prey groups comprised majority...

در این مقاله، هدف طراحی و ساخت سامانه تشخیصی پروب لانگمویر جهت اندازه ­گیری پارامترهای پلاسما دستگاه گداخت به ­روش محصورسازی الکترواستاتیکی اینرسی ایران (IR-IECF) به­ منظور مشخصه­ یابی چشمه‌­ی پلاسمایی می‌­باشد. بدین‌­منظور، یک برای اندازه‌­گیری مختلف از جمله دمای الکترون­، چگالی الکترون، یون، پتانسیل ساخته شده است. با نظر گرفتن مشخصات چشمه IR-IECF، الکترود مورد استفاده مفتول جنس تنگستن قطر طول...

Yellow perch (Perca flavescens) in Lake Michigan have experienced sustained recruitment failure since 1990 as a result of increased mortality during the pelagic larval phase. Increased mortality of larval yellow perch has been tied indirectly to increased alewife (Alosa pseudoharengus) predation, but effects of predation on larval survival variability must be better understood. We compared the ...

Investigations on juvenile American shad (Alosa sapidissima) revealed several physiological changes associated with downstream migration. Plasma chloride decreased 20% in wild juvenile shad during the autumn migration. Migrants had lower condition factor and hematocrit than non-migrant shad captured by beach seining. Gill Na+,K+-ATPase activity of migrant shad was higher than non-migrant; a 2.5...