There are programs in place to control both cats and rats, but both are very
resource intensive and don't offer long term solutions to either problem. While
these pests have been eradicated from some oceanic islands, Norfolk would
provide some pretty significant challenges in this respect for a number of
reasons. Firstly its size, roughly 8km x 5km, and its shape mean that it would
hard to bite off in 'chunks'. More than 2/3 of this island in private
ownership, a lot of it under agricultural use, and a population of about 1800,
which means that the social aspects of eradication are just as challenging,
perhaps even moreso, than the scientific ones.
The national park is only 15% of the island and even there, a huge amount of
resources is put in to just keeping the cats and rats at bay, the amount of rat
bait stations is currently being doubled to about 2000. The effort is showing
rewards, as outlined in the previous message, but a reduction in effort would
likely see that progress go backwards, and quickly, meaning that resources that
would be better spent in managing weeds and recovering the threatened plants
get perpetually tied up in feral animal management. The difficult financial
situation Norfolk Island has found itself in recent years also means that
control programs in the local reserves, such as Hundred Acres, have been very
limited.
It's not all doom and gloom however. Hopefully there will be moves to start to
tighten up some cat control in the coming years, even in my time here I'm
seeing a change in local attitudes. With regard to the rats, it will be
technology, not human effort, that eventually rids the island of its rats. With
no native land mammals at all, Norfolk would appear well placed for any future
rodent biological control, should such an effective mechanism ever occur. I
really don't believe rodents will be poisoned or trapped off an island of this
size, with so many people on it.
The recent boom of Bird Week attendances on Norfolk Island has been a great
reminder of the potential economic benefit of conserving our special local
species. The recovery of Phillip Island, which is without cats and rats, also
opens up opportunity to use it for back-up populations of Norfolk's species
there too. All four endemics previously occurred on Phillip Island, none are
there now. It also opens up the fascinating prospect of whether some species
that are now extinct on Norfolk Island but present elsewhere could be
re-introduced, but that's a much bigger question.
Craig Doolan
-----Original Message-----
From: Jenny Stiles
Sent: Thursday, 21 January 2016 4:58 PM
To: Doolan, Craig;
Subject: 2015 on Norfolk Island – the year in birds [SEC=UNCLASSIFIED]
Hi Craig,
Thanks for the detailed report about the birds on Norfolk Island. I was
wondering though as cats & rats are having a big impact on bird numbers and
breeding attempts if there are programs to control or eliminate them?
>From Jenny Stiles, Sydney
-----Original Message-----
From: Doolan, Craig
Sent: Thursday, January 21, 2016 1:27 PM
To:
Subject: 2015 on Norfolk Island – the year in birds [SEC=UNCLASSIFIED]
I thought it might be useful to pen a bit of an update on the year’s bird
watching and bird conservation highlights for our often forgotten little part
of the world. 2015 was my first full year on Norfolk Island so still plenty to
see for me and a few rarities turned up throughout the year.
Native bushbirds
It was another great breeding year for our Green Parrots (on the island the
Norfolk Island Parakeet and Crimson Rosella are referred to as simply ‘Green
Parrot’ and ‘Red Parrot’ and I’ll follow that convention here) with more than
70 fledged young in the predator proof nesting sites throughout the national
park. Sightings from outside the park appear to be getting more frequent
including far away. I live more than 2km away from the park, across farmland
and regularly get green parrots in my yard. Recently a flock of more than 20
was seen feeding on peaches in a property close to the park.
Hopefully we’ll have some firmer population figures soon, but the disastrous
2013 surveys which showed only about 45 birds seems a fair while ago now after
a couple of good breeding years. Red parrots are common over most of the island
although they are actively removed from the national park where they compete
aggressively for nesting sites with the green parrots.
For the other native bush birds, anecdotally we are being told there haven’t
been this many robins in years (note that the Norfolk Robin has just been
elevated to full species status in the latest IOC nomenclature) and they seem
to be benefitting from the extra cat and rat control inside the national park.
I have seen many, many young birds recently along the Summit Track, the easiest
spot to find them, and they are also enjoying the eucalypt plantations where
they are one of the more common species. Records outside the national park are
still very rare, and they appear to be unknown from the southern half of the
island.
I’m less certain about the status of Slender-billed White-eye with no real
inkling one way or the other as to which way it is going. They are still to be
seen in good numbers, sometimes in mixed flocks with the abundant Silvereyes,
especially along the eastern area of the park, and are in Hundred Acres Wood on
the south-west corner of the island, though seeming not over other parts of the
island. Another year has passed without anything resembling a good sighting of
White-breasted White-eye. It is now about 10 years since any reasonable
sightings of these birds. Despite being listed as vulnerable, the local form of
the Golden Whistler appears to be in very good numbers in the park and in
moderate numbers in some other parts of the island where there is forest,
native or otherwise. The NI Gerygone is common across most of the island while
the fantail is patchier outside the park, it is seemingly secure.
It was a good year for cuckoos with a sighting of a Pallid Cuckoo (admittedly
right at the end of 2014) and an Oriental Cuckoo. Shining Bronze-cuckoo are
sparse but present through spring and summer while there were quite a few
sightings of Long-tailed Cuckoos through October as the migrated. I didn’t hear
of any sightings in April on the way back. They are probably not uncommon but
given that they typically don’t call on the island they are probably missed. If
the Shining Bronze-cuckoos didn’t call, I doubt I would have seen a single bird
on the island yet. Masked Woodswallows still inhabit the island in reasonable
numbers with a flock of 26 observed at the airport and a single White-browed
Woodswallow was observed in December, the first seen for quite some time. The
two colonised the island at the same time in 1996 but neither have flourished,
but the Masked appear to have been the more successful of the two. Kestrels
appear to maintaining their modest numbers and I observed a cliff-side nest
near Cascade jetty while the kingfisher is abundant across the island and the
Emerald Dove seems to avoid the feral cats reasonably successfully.
Seabirds
Breeding seasons on Phillip Island and Norfolk Island have been steady for
Masked Booby and Red-tailed Tropicbird, both seemingly maintaining good
numbers. The Black Noddies and White Terns get hammered by feral cats in some
areas but with such large numbers of both, they seem to keep their populations
steady. The Grey and Brown Noddies seem to be restricted to Phillip Island and
costal islets where predation is less and they are in lower numbers. Despite
this, I saw winter flocks of 500+ of the Grey Noddies on Green Pool Stone off
the northern coast. Black-winged Petrels continue to be the most abundant
petrel and are commonly seen all over both islands in summer. They seemed to
have great breeding success on Phillip Island but their persistent attempts to
re-colonise Norfolk Island are met with failure through cat predation. That
said, I think it is only a matter of time until they do establish on Norfolk.
There are similar issues with the main island population of Wedge-tailed
Shearwater with significant predation and I think there probably needs to be a
question mark over the future of this population on Norfolk as a result. The
more rarely seen petrels, Providence, Kermadec and White-necked were all
observed on Phillip Island this year, and all believed to have bred there this
year, but beyond that we know little about their populations.
The increased regularity of frigatebirds around the island has continued with
12 Great Frigatebirds staying for a few months, roosting but not yet nesting,
on the Moo-oo Stone off the northern coast. They disappeared in winter and have
returned again this summer, their numbers doubled to a maximum count of 24. Up
until just a couple of years they were vagrants bought in by storms but they
are now regular. There are no adult males in the birds seen so far, so the
dispersal of younger birds could be a factor.
Time will tell if they establish here properly, where they could potentially
provide another predator issue? To the best of my knowledge there have been no
sightings at all this year of Australasian Gannets, that previously bred in
small numbers (<5 pairs) on Phillip Island.
There are also continued concerns about the Sooty Tern breeding population.
The 1000+ breeding pairs that used to be on Phillip Island largely up and left
for the 14/15 breeding season, and only a couple of hundred pairs returned in
15/16 year, around Moo-oo Beach, though there were smaller numbers in other
locations. Most have moved to the northern coast of Norfolk Island, especially
around Captain Cook’s monument. This is a concern because here they have to
contend with cats and rats where Phillip Island is predator free. Despite this,
and clear signs of predation by cats in some areas, at least several hundred
young were fledged from Norfolk in early 2015, mostly around The Cord, near the
national park. For the 15/16 breeding season, they have spread out a bit more,
on both sides of Captain Cook and so far, so good. The likely cause of the
desertion of Phillip Island was predation by Purple Swamphen who’s numbers have
increased across that island, though other birds they predate upon have
remained steady.
Feral birds
It has been a bumper year for chooks all over the island and their numbers
are at record highs. This poses great concerns for the invertebrate fauna of
the island, especially the 5 Critically Endangered land snails that occur on
the island. Probably not any noticeable difference in other species, though
I know I certainly saw more European Goldfinches as the year went on, but I
suspect that was more about them flocking in winter and me getting my eye
in. A flock of 40-50 Common Redpoll landed on the Summit Track in the
national park through August and September before dwindling to a few, just
as discussions were being had over whether they should be eradicated, and
then disappearing altogether. A Common Chaffinch was also spotted in
December, in a similar location, feeding with California Quail. I wouldn’t
say there had been any significant changes in other feral populations on the
island, though the number of feral ducks would have to be of some concern on
the few waterways. I have not seen any bird here that I would call a genuine
Pacific Black Duck.
Waders and other vagrants
Norfolk get’s relatively few waders outside of Pacific Golden Plover
(records of over 400 at the airport), Ruddy Turnstone (about 100 at the
airport), Whimbrel (rarely more than a few) and small numbers of Wandering
Tattler around the coast. During winter we had about 20 Double-banded
Plovers take up residence in the southern bays, especially Slaughter Bay.
Other recorded waders included a flock of 20 or so Red Knots in October, 3
or 4 Bar-tailed Godwits in late 2015, a single Sharp-tailed Sandpiper and a
snipe, presumably Latham’s, seen in October and December at the Kingston
Common. The Whimbrels and tattler appear to overwinter on the island.
A flock of 3 Oriental Pratincoles was resident at the airport through March
and April, about the same time as several White-winged Terns were there as
well. We also had a South Island Pied Oystercatcher at Kingston Common for a
few weeks in August and September. Oystercatchers seem to turn up every few
years and while historically several have been put to the Australian
species, I doubt these have been reliably identified and I imagine most
visitors would be SIPOs. A single Great Egret has been seen intermittently
on the island all year while the usual winter flocks of Cattle Egret turned
up briefly before also moving on. Also in winter were a couple of Swamp
Harrier, a normal winter visitor to the island, with at least 2 different
birds seen over several months. A couple of Little Black Cormorants were
observed on Cathedral Rock early in the year. Overall a good year on Norfolk
with more good news than bad on the bird front, a pattern that will
hopefully continue into 2016.
Craig Doolan
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