Bugs ‘n’ brates need saving too
Creepy crawlies and all those other little guys may be creepy and crawly, but comprise a truly integral portion of an ecosystem... So, let’s talk about New Zealand’s stream invertebrates.
We have all heard of the under threat whio and wrybill, but have you ever thought about what they eat? Often when we speak of conservation, we look at cuddlier creatures to which the public relates. Do not misunderstand, these birds are important to the ecosystem; however, we do tend to overlook the tinier species that are required for any successful ecosystem to perpetuate.
Most of us could list several species, unique to New Zealand, that are endangered, but I bet that not many of us could list many (if any) insects, crustaceans, snails or worms that are equally at risk as our water ways become less pristine.
Forest & Bird Manawatu is currently hosting a series of monthly lectures on freshwater conservation. The first talk in September had Andrew Watt from Horizons speaking on ‘Freshwater pests – their impact and control’ and how different introduced algae species are impacting on our freshwater ecosystems. The ultimate impact of course is on our native birds and fish.
The spread of weeds (e.g. didymo and hornwort) into our freshwater streams and rivers is displacing invertebrates from their natural habitats, leaving fish and birds without their food source.
Freshwater invertebrates are becoming well recognised as indicator species in determining the health of our waterways.
The composition of this minute community is shaped by a combination of physical habitat and water quality factors. Several studies have shown that the amount of fish at a particular site is significantly affected by invertebrate biomass, or population size. There are many programmes asking the community to pitch in and help identify and monitor invertebrates in lakes, rivers, and streams, so that we can learn more about our watercourses.
For an inside account of the integral part invertebrates play in our environment, all are welcome to hear Dr. Russell Death, Professor in Freshwater Ecology, Massey University, speak to Forest & Bird next Tuesday evening October 13 from 7.30pm, in City Library on George St.
Nesameletus – swimming mayfly nymph. An abundance of Nesameletus suggests good habitat and water quality conditions, especially if other mayfly or stonefly groups are also abundant.