Tagged: fish

A helping hand for migrating fish - Waiology

Waiology May 23, 2014

By Paul Franklin and Sjaan Bowie Many of New Zealand’s iconic freshwater fish species, such as whitebait and eels, undertake migrations between the sea and freshwater as part of their life-cycle. Whitebait, for example, lay their eggs in freshwater or estuaries before the larvae move out to sea after hatching (Figure 1). After a number of months growing at sea, … Read More

Water quality – What about the fish and the anglers? - Waiology

Waiology Oct 31, 2013

By Neil Deans New Zealand is blessed with an abundance and multitude of freshwaters which provide the habitat for an equally diverse array of species, including both native and introduced fish and wildlife. Some of these have intrinsic value; others are also valued because they provide food or recreational pursuit, or are indicators of a healthy environment. (Credit: … Read More

Effects of water quality on freshwater fish - Waiology

Waiology Oct 29, 2013

By David Rowe The presence and abundance of fish in our rivers depends on many factors, water quality being one. Water temperature, the amount of oxygen dissolved in the water, acidity (pH), ammonia concentration, and suspended sediment level can all influence the suitability of water for fish. When changes in land-use occur in river catchments, or pollutants enter waterways, … Read More

Rhombosolea retiaria: The freshwater flounder - Waiology

Waiology May 30, 2013

By Amber McEwan In lakes, rivers and estuaries throughout New Zealand, groups of aquatic flying carpets are mobilising and moving downstream towards the sea. Late autumn marks the time when a special species of New Zealand flatfish – the freshwater black flounder or patiki – embarks upon a spawning migration to the sea, with juveniles re-entering freshwater and migrating back … Read More

TOSP Episode 23: March 5th 2012 - The Sciblogs Podcast

Aimee Whitcroft Mar 06, 2012

Episode 23 of TOSP is _out_, yo! This week, aimee and Elf talk Mars, twisted radiowaves, a new livestock virus, the new number of neurons in a human brain (clue: it’s less than you might think), oxygen-generating biomaterial, SpeechJamming, meetings and IQ, using cellphone data following disasters, and the survival of the brightest. Read More

TOSP Episode 16: January 9th 2012 - The Sciblogs Podcast

Aimee Whitcroft Jan 09, 2012

Happy New Year! May 2012 be a wonderful year to you all. To start off the new year, aimee and Elf discuss last week’s announcement of the successful build of a temporal cloak, thorium’s potential as an alternative nuclear energy source and zombie bees! Also, we talk to fellow Sciblogger, … Read More

Lamprey – the vampire of the sea - Guest Work

Guest Author Jan 20, 2011

A shy, slimy, ancient fish, that looks like an eel but isn’t. It has a circular sucker for a mouth, and feeds by rasping a hole in its victim’s fishy-flesh. It starts life in freshwater, spends most of its life at sea, but returns to freshwater to breed. It can be found all around New Zealand, in southern Australia, … Read More

Kahawai, the people’s fish - Guest Work

Guest Author Jan 13, 2011

The second in a summer series from NIWA… Kahawai are an iconic species for recreational fishers. They are fantastic fighters and are found in most coastal waters, harbours, and estuaries around New Zealand, in both the North Island and South Island. Many New Zealanders will have memories of catching kahawai in the summer with their granddad, in a small boat, … Read More