Intertidal Surveys

March/April

I have been incredibly lucky to have been included in the team from Taranaki Regional Council who are monitoring the state of the environment by doing intertidal (between low and high tide mark) surveys. 

Every year they go to the same sites at very low tide.  They lay out a 50 metre tape in a straight line along the sea shore.  This is called a transect.

The tape is put in exactly the same place each year.  Photos and GPS points are used to help with this.  We look at 25 places (randomly selected by computer) along the transect line.

But first Emily, the marine biologist (a scientist who has studied things that live in the sea), puts some knee pads on (some of these rocks are sharp).

We place the quadrat and record the substrate, this is what the surface is made of: it may be boulders, rocks,  cobbles,  gravel,  sand or silt and mud.  Often it is a mixture of these things, so we write down how much of the quadrat is covered.

Then we do the same thing for algae (like seaweed), then barnacles and worms.  

Then we get to look for shellfish, crabs, little fish, starfish etc.  

The more species in a quadrat, the longer it takes.  

It is interesting to see the differences in the number of species on different parts of the coast (this is called biodiversity).  

Emily takes photos when she finds something particularly interesting.  Sometimes she finds something she cannot identify.  When this happens, she sends the photo to other scientists to see if they can help her.

  

We have  to make sure we finish before the tide comes in. 

We saw some interesting things on our way to the site.
This is a fossil, probably a scallop shell.

It is important that these surveys are done so that we can look to see if there are areas which may be changing and why.  

We must make sure that we do not pollute our marine environment.  One of the first signs that this might be happening is when we notice changes to the species on the seashore.

Some of the places we go to are really hard to get to because they might be a long way away from a road and beside cliffs.  When this happens we use a helicopter!