Newsletter #77
Bird surveys
- 2022: Waiau River
- 2023: The following are some observations by Grant Davey:
Opihi River mouth
- Around a dozen banded dotterels, flocks of pied and spotted shags, one spoonbill, several pairs of variable oyster catchers, and small number of Southern black-backed gulls.
- Up to 10 black fronted tern (BFT) fledglings, possibly from nests near the mouth, but ID hard as adults are losing breeding plumage and last year’s chicks are around. (Didn’t see any BFT further up the river.)
- Large number of black-billed gull (BBG) fledglings, with a flock of hundreds of white fronted tern (WFT) behind them – including some fledglings. A 4wd drove past, disturbing the BBG – the driver didn’t stop, just turned around and drove back out.
- Around 1,000 BBG nests, a few birds were still on nests, and chicks ranging in age from a few days to well advanced fledglings. Numerous RBG amongst the BBG.
- On the horizon, what looked like BBG and WFT colonies on the top of a high gravel ridge.
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Paul Saga also observed these colonies some 6 weeks earlier: 30 November – the water level was high, but I managed to scope the gulls and terns nesting on the gravel bar to the north of the open rivermouth and estimated 1000 (500 breeding pairs) black-billed gulls and 1600 (800 breeding pairs) white-fronted terns. That said, I could not see all of the birds because of the undulating gravel bars. The results were submitted to eBird on 30 Nov and are available to all.
- Immediately south of the BBG colony is a WFT colony – probably similar number of nests. Most chicks were fledged or almost so, but there were a few smaller ones and perhaps a few birds still on nests.
- Two fishermen, with a dog on leash, walked through the fledgling birds and there was a lot of evidence of vehicles.
- Immediately north of the BBG colony, tracks indicate some have driven a few metres to the west of the colonies. Along these tracks there are around 20 dead young gulls – obviously they had been hit by cars. They were mostly near fledgling size, but also a few small chicks. There was also an injured WFT chick.
It seems clear that nobody has been keeping an eye on this area. This place deserves at the very least some large permanent signs as a starting point.
Opihi other
- There is still good open gravel at the old gravel extraction site a few kilometres upstream from Pleasant Point – but we saw no birds at all.
- Immediately upstream from the PP bridge is active gravel extraction. This could result in some nice braiding and weed clearing on islands Could be quite nice for next season – the islands might be a bit small though. We saw no birds here.
- Just up from Mill Road, ECan has rebuilt a stopbank and have done a lot of dozing in the river. Flock of 45 SIPO, about 20 stilts and 100 plover nearby. Just upstream were about 10 SBBG.
- No birds at Kerrytown Road.
Lower Waitaki
- Kurow island is vegetated, mainly long grass, down to the river – flow was high. Restoration of the island has apparently not included weed management. Unusual to not see BFT flying along the river here.
- Possibly a BBG colony in the Waitaki about 32km downstream from Kurow. The river at SH1 looks shocking, weedy, with a lot of willow logs.
- River mouth – lots of SBBG and a few spotted shags.
Ashburton
- Sizeable BBG colony around 500m downstream from the bridge – (03 January) in danger of being flooded out.
Rakaia
- Smaller BBG colony couple of hundred metres downstream from the bridge.
Orari (from Tony Doy, early December 2022)
- Good-sized colony of BFT/BBG at Vance Road. Normally they would’ve failed by now due to drying up braids, but heaps of water right past Vance Road.
News
- In a desperate effort to save a seabird species in Hawaii from rising ocean waters, scientists are moving chicks to a new island hundreds of miles away. -AP News
- Avian flu is on the rise. “Wild birds are now permanently infected.” While it’s still mostly in the Northern Hemisphere, and nothing we can do given the number of migratory birds that travel to Aoteaora, this is something to be aware of.
Reports and research
- Sananz, The effect of anthropogenic disturbance on braided river birds in New Zealand, PhD Thesis. This is embargoed for some time, to give Sanaz an opportunity to publish, but I’ve loaded the abstract here, and if you’d like more details, you can email her: safavian [dot] sanz [at] gmail.com. (Not hot-linking her email to save her from possible spam).
- Tonkin; Climate Change and Extreme Events in Shaping River Ecosystems; Encyclopedia of Inland Waters, V2, pp653-664
- McCarthur et al., State and trends in the abundance and distribution of riverbed-nesting
shorebirds on the Tutaekuri, Ngaruroro and Tukituki Rivers, Client report prepared for Hawke’s Bay Regional Council, Napier - McCarthur; A review of significant coastal and freshwater habitats for indigenous birds in the Wellington region, report prepared for Greater Wellington Regional Council
- McCarthur; A review of the shorebird values and management actions in Hawke’s Bay
Regional Council’s Ecological Management and Enhancement Plans - McCarthur; A review of the status and management of banded dotterels (Charadrius bicinctus) on Ōnoke Spit, Client report prepared for the Department of Conservation, Masterton.
- Suckhodolov et al, Mixing dynamics at river confluences governed by intermodal behaviour Nature Geoscience 16, pp89-93, 2023
- Battin et al; River ecosystem metabolism and carbon biogeochemistry in a changing world, Nature 613, pp449–459, 2023