Saturday, 31 October 2020

Heron Island- The Amazing Birds and Sea Life

 

Welcome to Heron Island

Heron Island sunrise
Our arrival on Heron Island on October 18 till 23, coincided with the nesting season of the White Capped Black Noddy Tern, Anous minutus  which arrives to breed on the coral cay islands from October to January.   Normally 30-70 thousand pairs breed on the island, but have had up to 120 k pairs.  The preferred nesting tree is the Pisonia tree which only grows on coral cays.  Every tree had multiple nests. The Pisonia tree has an unusual relationship with the terns in that at the end of the nesting season in January its seeds become very sticky and trap some terns and other birds to the extent that they can no longer fly and starve to death only to serve as fertiliser for the hungry trees.

The Noddy nests are a very rudimentary structure of  dead Pisonia leaves and bird poop,  The males collect leaves and present them to the females for consideration.  She may accept or reject the leaves by dropping them.  Some males have found that dipping the leaves in sea water makes them more acceptable. The Noddys generally raise 2 chicks one after the other.  If the first chick dies the female divorces the male and finds another mate for the second attempt. 
Noddys Anous minutus feeding at nest

 Also nesting on the island at this time is the Wedged Tailed Shearwater Puffinus pacificus which nests in burrows about 2m long all over the island.  At night you need to watch where you tread as they tend to lay outside of the burrows and are easily trod on.  The vision of the shearwaters is like polarised sunglasses and this makes them almost blind on land at night.  Together with rear positioned legs they are prone to bump into trees etc when coming in to land at their burrows.

The common nesting Tern is the Bridled Tern Sterna anaethetus  a ground nester.  

Bridled Tern in flight


Bridled Tern  Sterna anaethetus 

Most of the birds simply ignore you as you pass or hop a meter out of your way.

Less friendly are the Eastern Reef Egrets Egreeta sacra  who tend to have a wider comfort zone of 3-5m.  Both the light and dark forms are present in large numbers and are also nesting at this time and have large hungry chicks.  The chicks are not friendly to each other and generally only one will survive to fledge.

 

Eastern Reef Egret Egreeta sacra


Eastern Reef Egret chick on nest


Eastern Reef Egret Egreeta sacra dark form

The Buff-banded Rail Gallirallus philippensis is very common on the island and have distinct defended territories in which they lay up-to 11 eggs, but usually only one or two will survive predation by the Egrets and gulls.  The mothers are very protective but are unable to deter the hungry Egrets. 

Buff-banded Rail Gallirallus philippensis

Rail with chicks

Capricorn Silver-eye Zosterpos chlorocephala
This is a distinct Barrier Reef island form, yellower above, whiter below.  It does not interbreed with the more common Zosterpos familiaris which occurs in eastern Australia as far north as Rockhampton.

Ruddy Turnstone Arenaria interpres
The Ruddy Turnstone were in non-breeding plumage.
Ruddy Turnstones - in flight

Grey-tailed Tattler Tringa brevipes
Grey-tailed Tattlers breed in Siberia.  When feeding, they dart about bobbing and teetering between runs in their search for crabs, mollusks, sometimes fish.
Pied Oystercatcher Haematopus ostralegus
Pied Oystercatchers mate for life and are unable to survive as a single bird.
Brown Booby Sula leucogaster
The Brown Booby is a bird of the tropical oceans and ranges, in Australia, from Brisbane north to Dampier in Western Australia.  They prefer to roost on solid objects and nest on the ground.  This particular bird had lost its mate.
Black-naped Tern Sterna sumatrana
This tern breeds in colonies on rocky islands and headlands.
Black-naped Tern

During a walk at dawn on the beaches, you will find laying Turtles both Green Chelonia midas and Loggerheads Caretta caretta.   More often one just finds tracks as most turtles have returned to the sea by daybreak.

Up the beach

Green Turtle track up the beach.

Nest sites

Green turtle nest site along side a protected Loggerhead turtle nest. The Loggerhead turtle is Critically Endangered so the nests are protected when found. 


Job done!
A female Green Turtle returns to the relative safety of the water.

On the Reef

Shark Ray Rhina ancylostoma


Eagle Ray Myliobatis australis
Very common around the jetty and shallow reefs around the island.
Manta Ray Manta alfredi
Manta Rays are classified as Vulnerable, largely due to overfishing.  Other threats include climate change, sediment run-off, pollution, rising sea temperatures.
Epaulette Shark Hemiscyllium ocellatum
Frequently seen while one is enjoying walking on the reef.
Black-tipped Reef Sharks
Many types of coral can be seen during the glass-bottomed boat cruise.  Identification remains elusive.



Sea cucumbers

Starfish on reef


Wreck of HMCS Protector

On 19 June 1884, HMCS Protector was ready for service. In July 1943, en-route to New Guinea for service with the US Navy and off Gladstone, she was damaged in a collision with a tug and abandoned.  The hull was taken to its present place at Heron Island and later sunk for use as a breakwater.
Sunset over the wreck
Text & Photographs: Ian Smith













 


 


















                          

                                              








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