Towra Point Report

Towra Point Report
By Julian Burst

Introduction

This report is based on the Towra Point Nature Reserve, in Kurnell. On our excursion, we got detailed information on various bits of information about organisms such as plants like mangroves, and animals such as the Soldier Crab and many species of birds and spiders. Things such as the types of Trophic Interactions show the levels of species and to clearly show what species is a stronger predator then the other.

With the use of mathematical formulae, we are able to find out the population % of mangroves and the average population of a soldier crab in certain areas. Soldier crabs alongside other species fight for resources, and this can have drastic short and long term consequences. Even small
We then checked the areas checked by the quadrats in 17 random areas on the map determined by a random number generator and counted how many of the 5x5 quadrat’s squares contained mangroves and recorded a percentage cover, giving us an estimated percentage cover of mangroves over all of Towra Point.

17 different areas were randomly picked out in our results, and by calculating the percentage cover of each individual point, adding them all together and then dividing by the amount of places we checked, we got an average percentage cover over Towra Point of 70.4% (Table 6) . Towra Point’s Nature Reserve is approximately 603.7 ha, or 6.037 km2. Using our average percentage cover of Towra Point of approximately 70.4%, we can now deduct that the average mangrove covering over all of Towra Point is 425 ha, or 4.25km2.
(NSW Government, 2010)

Table 6 - Percentage Cover of Mangroves in Towra Point
21/25 = 84%
14/25 = 56%
23/25 = 92%
17/25 = 68%
19/25 = 76%
5/25 = 20%
9/25 =
On Figure 5 we can see the area of Towra Point, and get a look at how the mangroves are distributed in the area. The mangroves poke out of the mud at shorelines at Towra Point and the roots allow the plant to breathe.
(SSEC, 2004)

Figure 5 - A Birds Eye view of Towra Point (Google Maps, 2015)

Mangroves are only found in Estuary systems, which are when freshwater and saltwater mix. The Georgia River and The Cooks River are two rivers which travels towards Towra Point, mixing with the open ocean water. As there aren’t many Estuaries in Australia, there are only Mangroves in select areas and this is a reason that Towra Point is a Nature Reserve.
(Ocean Service, 2008, AUSECO, 2014)

Animal Population Abundance

At Towra Point, wild animals were captured with the use of pitfall trapping, which is a pit in the ground that when an animal steps on top of it, it will release and the animal will fall into the pit, and it won’t be able to