Continuous Plankton Recorder

The Continuous Plankton Recorder (CPR) is a scientific instrument designed to collect plankton samples from the ocean over extended periods and distances. It is a crucial tool in marine biology and oceanography for monitoring the abundance and distribution of plankton, which are vital components of the marine ecosystem.

History

The Continuous Plankton Recorder was first developed in the early 20th century by Sir Alister Hardy, a British marine biologist. The initial design was created to study the distribution of plankton in the North Sea. Since its inception, the CPR has been used extensively in various oceanic regions, providing valuable data for understanding marine ecosystems and the effects of climate change on oceanic life.

Design and Function

The CPR is towed behind a ship at a depth of about 10 meters. It consists of a robust metal frame housing a silk filtering mesh that captures plankton as water flows through the device. The mesh is wound onto a spool, which is advanced by a propeller-driven mechanism, allowing for continuous sampling over long distances.

Components

• Frame: The outer structure that holds the internal components and protects them from damage.
• Silk Mesh: A fine mesh that captures plankton from the water.
• Spool and Propeller Mechanism: Advances the mesh to ensure continuous sampling.
• Flow Meter: Measures the volume of water passing through the device, allowing for quantitative analysis of plankton density.

Applications

The data collected by the CPR is used in various fields of marine science:

• Biodiversity Studies: Understanding the diversity and distribution of plankton species.
• Climate Change Research: Monitoring changes in plankton populations as indicators of climate change.
• Fisheries Management: Assessing the health of fish stocks, as many fish species rely on plankton as a primary food source.
• Ecosystem Monitoring: Tracking changes in marine ecosystems over time.

Data Analysis

The samples collected by the CPR are analyzed in laboratories where plankton species are identified and counted. This data is then used to create maps and models of plankton distribution, which are essential for understanding oceanic processes and the impacts of environmental changes.

Advantages and Limitations

The CPR provides a cost-effective and efficient method for large-scale plankton monitoring. However, it is limited to surface waters and may not capture deeper-dwelling plankton species. Additionally, the identification of plankton species requires skilled personnel and can be time-consuming.

Also see

• Plankton
• Marine Biology
• Oceanography
• Climate Change
• Fisheries Science