Programs for ecologists by PISCES Conservation Ltd
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.
Density from Distance
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.
, 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
Copyright 2004 PISCES Conservation Ltd