Programs for ecologists by PISCES Conservation Ltd

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It contains three easy to use methods: constant & variable probability of capture

(Zippin s maximum likelihood, ML ) and a regression model.

Using the ML methods the program can calculate a population estimate, the upper &

lower 95% confidence intervals & the probability of fit of the model.

The program allows instantaneous graphical comparison of the various methods &

rapid sub division of the data. Data from spreadsheets such as Excel can be imported

as CSV files.

Removal Sampling is particularly useful for:

1  The estimation of fish densities using data collected by electric fishing:

2  Small mammal population estimation using traps.

3  Studies on insects that live in small, discrete populations that can be sampled

using techniques such as sweep netting or pitfall traps.

12.8

Density from Distance

DfD

 is a Windows program offering a range of analytical techniques commonly used

by ecologists to estimate animal and plant density from measurements of the distance

between objects or from a selected line or point to the objects. DfD has been

designed for ease of use on PCs running under Windows. While designed for research

use, the program is particularly useful for ecological teaching because it allows

students to quickly enter or simulate data and explore a range of methods within a

familiar Windows setting. The program is particularly useful for botanists and

zoologists studying birds or large mammals.

12.9

Dynamica

With 

Dynamica

, users can explore real data, and reach their own conclusions about

how animal numbers are inter related and change through time. The data consist of

monthly abundance estimates of fish and crustaceans from January 1981 to January

1995, at Hinkley Point power station, Severn Estuary, UK. Time series for more than

one hundred species are available for study. Details about data collection and habitat

are also given. Dynamica was designed as a research tool to help explore the complex

inter relationships between species and environmental factors such as temperature,

salinity and tides.

The strong theme running through Dynamica is the study of community level

dynamics. Books often portray communities and food webs as static entities. This

program will show you just how dynamic food webs are. Perhaps the most popular

community statistic is a diversity index; Dynamica will let you compare different

indices and appreciate how they change through time.

Dynamica has been designed to be useful to anyone with an interest in natural time

series. It presents a range of elementary techniques for time series analysis, including

data transformations, autocorrelations, moving averages and Fourier analysis. The

program presents a wide range of natural dynamic behaviours which make good

examples for study.

More information is available on the Hinkley Point sampling on our website at

http://www.irchouse.demon.co.uk/consultproj1.html

Copyright 2004  PISCES Conservation Ltd