Aims and objectives
The main aim of this module is to introduce students to the use of a wide range of practical equipment and techniques in the context of fieldwork based mainly on a large, deep lake. Part of the course culminates in the production of a poster describing a group project; a subsidiary aim is therefore to develop teamwork and communication skills. The module builds on BS20620, in which the coverage of limnology is largely lecture-based.

Content
The course is residential at University Field Station, Rowardennan. Much of the practical work is based on Loch Lomond, and on an adjacent, smaller lake, Lochan Dubh. In each part of the course practical work is preceded by lectures introducing the practical assignments.

A substantial part of the course is devoted to the investigation of the relationships between physical conditions and the distributions of macrophytes and invertebrates along loch shore transects. This involves the use of small boats, employment of simple surveying techniques, sampling by a variety of techniques including an Ekman grab, and identification of material using `professional' keys. Students work in groups and prepare a group poster and a reference specimen collection during the course. Poster production involves the use of computers to analyse results and to prepare text and graphics. Peer assessment forms an element of the mark for this part of the course.

Again working in groups, students spend a day working on the open water limnology of the north and south basins of Loch Lomond. Here they prepare depth profiles for temperature, light and dissolved oxygen, taking additional samples by van Dorn sampler for measurement of conductivity, pH, nitrate and phosphate. Phytoplankton samples are collected by a variety of techniques and examined in the laboratory for species composition and biomass estimation by chlorophyll a analysis. Zooplankton composition and abundance is characterized from material collected in simple plankton nets and in a Clarke-Bumpus sampler. This part of the course is assessed on the basis of individually-written reports submitted during the first semester.

Work on lake fishes includes a lecture on fishery assessment and the setting of gill nets in both Loch Lomond and Lochan Dubh. In the laboratory, fishes captured are identified and measured. Ages are determined from scales or opercular bones, and sex, reproductive condition and diet from dissection. Normally, the course includes a day spent at the Institute of Aquaculture, Stirling and at their hatchery and rearing facilities. This part of the course is assessed on the basis of a report submitted at the end of the course.

Learning outcomes
On completion of this course, students should be able to

• operate safely and effectively a wide variety of sampling and environmental sensing equipment in field conditions
• apply appropriate analytical techniques to aid interpretation of the data they obtain
• have improved their ability to communicate their conclusions in poster form
• have identified a variety of freshwater algae, macrophytes, invertebrates and fish to species level
• will have acquired the knowledge and skills to enable them to attempt the identification of almost any unknown specimens from freshwater habitats
• have improved their understanding of the benthic and open water communities of lakes.