Several nature-like fishway designs have been constructed in the northeastern US, but none of these fishways have been quantitatively evaluated for passage of northeastern diadromous species. This report summarizes data on passage performance from two studies of nature-like fishway designs for passage of river herring in the field (Town Brook, Plymouth, Massachusetts, and East River, Guilford, ...

Recent studies have shown that some clupeid fishes, including shad and menhaden, can detect ultrasound (sound with frequencies higher than 20 kHz) and actively avoid it. However, other clupeids, including sardines and anchovies, do not detect ultrasound. The hearing abilities of herring are of particular interest because of their commercial importance, our reliance on acoustics to monitor their...

In this paper, we analyze the connections between the different qualitative properties of numerical solutions of linear parabolic problems with Dirichlet-type boundary condition. First we formulate the qualitative properties for the differential equations and shad light on their relations. Then we show how the well-known discretization schemes can be written in the form of a one-step iterative ...

This paper describes a project that was done for the Shad Valley Program, where it was required to assign students to seminars so as to maximize the satisfaction of the students with their assignments. We begin by describing the problem, its inputs and constraints. Two models are proposed to determine optimal assignments. The first model is based on the Capacitated Transportation Problem and a ...

The distribution of purines and pyrimidines in desoxypentose nucleic acids prepared from a variety of animal and plant sources has been studied. 1. The nucleic acids were prepared from calf thymus, calf kidney, sheep spleen, horse spleen, chicken erythrocyte, turtle erythrocyte, trout sperm, shad testes, sea urchin sperm, wheat germ, and Pneumococcus Type III. 2. Separate hydrolyses were carrie...