This classification method enables the assessment of invertebrates in rivers in relation to general degradation, including organic pollution. Whalley, Hawkes, Paisley & Trigg (WHPT) metrics replace the Biological Monitoring Working Party (BMWP) metrics used for status classifications in the first river basin planning cycle.
Benthic invertebrate communities are good indicators of acidification which is caused by acidic pollution from precipitation and acids leaching from the surrounding soils. They are easily suited to biological monitoring as they are common, widespread and easily sampled.
Dogwhelks are a good indicator of the contamination of the hazardous substance called tributyltin (TBT) which used to be used in anti-fouling paints on the hulls of large ships.
Benthic invertebrate communities are good indicators of organic pollution and are also sensitive to toxic pollutants. They are ideally suited to biological monitoring as they are sedentary and either feed upon sediment dwelling animals or the sediment .
Aquatic benthic invertebrates, of which chironomids are the largest family, are good indicators of nutrient enrichment and can be used to assess lake water quality. Passively drifting pupal skins accumulating at the lake leeward shore are easily collected.