The tarāpunga that nest under the Panmure Bridge are heavily impacted by humans, the national population is in decline. While deploying a nesting structure for tara / white-fronted tern yesterday we also added a small extension to the Panmure tarāpunga nesting structure. We upcycled old wood which fitted the rustic nature of the old bridge. The six nesting areas were c35cm x 25cm. The gulls were already a few weeks into nesting with some three eggs nests. As the colony is currently space limited I think the structure will help, but we may have been a bit late deploying. The gulls also nest on boats in the estuary so if some get disturbed they may move to the main colony. It was promising to see two gulls having a tussle over the new nesting area while we exited the estuary.
Photo taken 5:30pm 18 September. Gulls regularly seen on the platform, but not sitting.Photo taken 2 November. Success!Photo taken on pole camera shows six nests.
I checked many old boats moored in the Estuary and did not find any with nests which is great. One pair of gulls nested on a post, another on a jetty where it’s likely to be disturbed. There is a clear case for extending the nesting platform in 2023.
This photo of a parent attending a chick in the current upstream from the colony indicates there may be some benefits to creating a ramp of sorts for the juveniles.New addition added. Noted 8 infertile eggs on site, one dead chick, two chicks remaining, no dead birds with fishing line attached but any bodies may have been blown into the estuary by the cyclone. Some fishing line removed from site. One fledgling was in the water and calling, it would be good to have a ramp or additional floating area(s), this may reduce chick mortality and would definitely reduce colony stress.
Added some extensions after taking this video (30 September 2004)
This one has quite tight spacing (c25cm) but I know from the tara next box experiment it will not be a problem.We ran out of wood and this large platform only has one divider, it will be interesting to see how many gulls still want to use it.Both new platforms utilised. Photos October 10 2024 by Matt Rayner.
Tarāpunga / red-billed gulls (Chroicocephalus novaehollandiae scopulinus) and tara / white-fronted tern (Sterna striata) nest on artificial structures in the Tāmaki Estuary, Auckland, New Zealand. The Department of Conservation ranks both species as At Risk / Declining (Robertson et al. 2021). Both species have also nested on moored boats in the estuary which creates human-wildlife conflict.
Piles under Waipuna Bridge (middle, photo taken from land). Photo by Shaun Lee.Piles under Waipuna Bridge (western end, photo taken at low tide). Photo by Shaun Lee.
Hypothesis
A nesting platform on the large piles (72cm diameter) that rise c2m above Mean High Water Springs (MHWS) under Waipuna Bridge. The piles are safe form mammalian predators who could not swim then climb to the nests. This area is less impacted by light pollution than Panmure Bridge where there is a tarāpunga colony.
Challenge
Solution
The nests are exposed to avian predators including the adjacent tarāpunga.
Using vertical canes to stop flying attacks on chicks. See Preston Dock Common Terns below.
The nest structures might be used by tarāpunga.
This is not a poor outcome but if the spaces are deep and small they might not be so suitable for tarāpunga. There is a small chance that nearby nesting feral pigeons are also interested in the structure.
Colonies are ephemeral (McLean 2018) with birds moving regularly.
This could be an advantage as species with higher site fidelity would be harder to attract. Suggest the addition of a 3D printed decoy to improve the chances of success I the first season.
The structure will attract human attention.
Clearly label the structure as a ‘trial bird nest for endangered terns’ include a phone number & URL to a blog post about the project. Centre the decoy to keep it less accessible / visible to humans. The height of the piles will help deter vandals. Even at low tide access requires a boat or a swim. Graffiti on the bridge may have been enabled by retired pontoons.
Installation difficulties
The piles are tall and using a ladder on a boat is tricky. A platform that connects the piles is visible 2.5hrs after high tide at the western end. A ladder could be used on the platform but it will be slippery.
Monitoring
There is no pedestrian access to the bridge. A land based site inspection from Finn Place identified the western piles as easy to monitor.
Preston Dock Common Tern nest boxes made by the Fylde Bird Club in Lancashire.
Tara do not use nesting material (NZBirdsOnline), a small amount of sand could cover the floor of the nests. The Preston Tern Nest Boxes use gravel. Drainage holes should be added to keep water out.
Proposed design
Based on the Preston Dock Common Tern nest boxes. Tara are not much larger than Common Tern but we have made the nest boxes smaller to dissuade tarāpunga form nesting here. Boxes dimensions made of ‘Radiata Premium Grade Smooth Decking 140 x 32mm’. The extra depth allows for a max of 40mm of gravel.
How the nest boxes might attach to a platform on top of the piles.
Timing
Tara tend to arrive at a prospective nesting location only a few days before laying, and there is a high degree of synchronisation of laying within a colony (NZBirdsOnline 2022). Eggs are laid between October-December (NZBirdsOnline 2022). Prospecting may begin weeks before egg laying. We plan to deploy the structure by mid September.
Deployment
The structure was deployed on the 14th of September 2022 (with a few modifications). I had a huge amount of help from a friend who is much more handy with an impact driver than me. The decoy is a bit odd looking as its just a scaled up tara iti with a different paint job. Five tara flew past while we were working and roosted on the piles in the center of the channel. We decided not to deploy the canes until we had active nests.
Update 15 Sep 2022. 10:00am-10:45am.
Four tara and three tarāpunga were roosting on the piles in the centre of the estuary. Every ten minutes or so they would be quite loud with both species calling and jostling for space but no confrontations observed. There were three close passes of the decoy and on at least two of these occasions it seemed like the terns were calling at it. No terns landed on the boxes but both species visited the piles near me. One tern was foraging from a pole which gave it a good view of any fish swimming above the platform in the shadow of the bridge, but it did not dive. One tern dived on in the centre area.
Update 18 Sep 2022. 5:15pm-6pm
About three gulls regularly on the piles in the centre of the estuary. Lots of gull movement and calls, more gull activity between the bridges than the 15th. No terns seen.
Update 28 Sep 2022. 2:15-2:20pm
Constant red-billed gull activity. Three gulls roosting on centre piles. Two pied shags feeding on the southern side.
Update 10 Oct 2022. 1:00-1:01pm
Low tide, no activity. Just a pied shag foraging under the bridge.
Update 23 Oct 2022. 5:00-5:01pm
High tide, no activity. Just a few gulls roosting on centre piles.
Update 02 Nov 2022. 1pm.
Photo taken from pole mounted GoPro shows gulls are prospecting the nest boxes.
Two pairs of tarāpunga have nested in the boxes. One of them has really filled it up with material!Tara also look to be nesting in an adjacent boat.
Update 23 Dec 2022. 12pm
The first pair of gulls have a chick, the second nesting gulls have not increased their nest height at all. Maybe because the other pair can keep watch.
Update 15 Jan 2023. 5:30pm
I’m hoping the chick is in one of the nest boxes and the second nest is not being sat on because it is hot, and the nest has a chick. Alternatively there is another adult down in the nest box. If the recent storms had destroyed either nest or pushed the chick off the adults would likely have moved on.
Update 18 Feb2023. 5:00pm
The structure is cyclone proof! Weather stations at St Helier’s and Howick recorded wind speeds of 40 knots (74kph). Despite the roosting gulls in the photo I dont think there were any active nests on the structure today.Additional visit 22 Feb shows nesting material in five of the six boxes. To my knowledge only the two with the most nesting material were used for nesting.
Update 22 Nov 2023. 11:00am
The gulls nested here earlier this year with a chick ready to fledge already. It also looks like at least three of the nest boxes were utilised. There was also a juvenile on a nearby boat and on a pylon under the bridge where tara nested last year.
Update 28 Jan 2024. 2:00pm
The gulls are still using the platform for nesting even though there is space at the main colony. I think the design is just too appealing to gulls.
Update 29 Sep 2024. 3:40pm
Gulls continue to dominate these nest boxes and it looks like three pairs are having a go here this year. Time for Plan B.
Plan B
Matt Rayner had the idea to add concrete tree rings to the tops of the poles. On the 30th of September 2024 we deployed four pairs of tree ring semicircles to the tops of the poles and added shell to encourage nesting tara. They were deployed on the group of poles next out from this group to avoid disturbing the gulls. There are three on the northern side and one in the south where we have seen tara try to nest unsuccessfully in the past.
Nest 1. Northern side, most eastern nestNest 2. Northern middle nestNest 3. Still on the north side of the bridge but further south than the other two nests. We added more shell to this nest to see if that makes a difference.Nest 4. Southern pole had a small metal (rusting) rim
Update 12 Oct 2024. 2:23 pm (windy)
All tree rings had single gulls hunkered down in them. Presumably nesting.All these nest boxes are now full for the first time.
Update 18 Nov 2024. 10:30 am
Also had fledgling gull in the water.Two out of four tree rings had gull nests. A gull is also nesting on and adjacent pole with no tree ring for the first time.
Robertson et al. 2021. Hugh A. Robertson, Karen A. Baird, Graeme P. Elliott, Rodney A. Hitchmough, Nikki J. McArthur, Troy Makan, Colin M. Miskelly, Colin. J. O’Donnell, Paul M. Sagar, R. Paul Scofield, Graeme A. Taylor and Pascale Michel. Conservation status of birds in Aotearoa New Zealand, 2021. New Zealand Threat Classification Series 36. Department of Conservation, Wellington. 43 p.
Mclean 2018. Successful restoration of an unnatural breeding habitat for white-fronted terns (Sterna striata). Notornis, 2018, Vol. 65: 54-58. The Ornithological Society of New Zealand Inc.
Yesterday I checked about 10km of beach for kekeno / New Zealand fur seals in Mercury Bay , Coromandel including Wharekaho, Kuaotunu, Otama, Opito, Matapaua. I did not find any alive or dead. The beaches were largely empty but I did ask five locals to keep an eye out and report them as part of a study I am helping DOC with in the area. One person was aware of the study.
I noticed a few bits of fishing line washed up on the high tide line left by dirty fishers at Wharekaho / Simpsons Beach. I picked up all the bits I could find for 1km East of Stormont Lane. I counted 57 bits of rubbish, many were tangled knots of nylon which pose a danger to shorebirds who can get their toes caught in it (see photo above).
Dotterel counts for the above beaches logged on iNaturalist.nz
I have been helping hapu, iwi and community oppose massive sand mining consents in Pakari. I made this before and after graphic after reading the reports on the size of the trenches and seeing the lost biodiversity. It’s been used in this beautiful little video by Better Ancestors.
Here are some more graphics that I made for the Department of Conservation’s awesome Marine Ecosystems Team. I have published them all here, as a reference. You can download them on their website here and here. I posted the previous batch of graphics I did for the series here.
The New Zealand Underwater Association’s (NZUA’s) Annual report is out with lots of stunning photos from Experiencing Marine Reserves. I do a lot of diving but I’m not a member of NZUA. One of the reasons for this is the associations close relationship with the blood sport organisations (New Zealand Sports Fishing Council / Legasea and The NZ Spearfishing Association).
Environmental campaigns are one of its three pillars but the organisations moral compass is compromised by support for activities that kill our native wildlife. They have been more political recently (lobbying government on fishing policy) but they aren’t developing their own views, just kowtowing to Legasea.
On page 26 of the Annual Report they have said they will be consulting on new Marine Protection Areas (MPAs) and that they support them, but they give some uninformed caveats.
We don’t support MPAs where:
1) An area is not of ecologically significant (This is the exact wording, not a typo from me)
This is an illogical statement because we need to protect a network of representative habitats from fishing. In Aotearoa / New Zealand less than a one percent of our marine environment is protected from fishing, so nearly any protected areas will become ecologically significant.
2) Where removing an area concentrates fishing effort elsewhere
All place based fishing protection displaces fishing effort, including those that limit commercial fishing. It’s a short term loss that is offset by the long term benefits of having an area with larger breeding animals which produce exponentially more offspring. For example it takes thirty six 30cm Tāmure / Snapper to make the same amount of eggs as one 70cm fish (Willis et. al., 2003). And of course the spillover effect which I should not have to explain.
Despite our Marine Reserves being the best places to dive, NZUA say that ‘instead’ they will now support Special Marine Areas (SMAs). They then confuse the term as used in Revitalising the Gulf: Government action on the Sea Change Planand tell readers that SMA’s include the mussel beds that I have been helping to make (which are not protected from human harvest), seaweed reestablishment and crayfish re-introduction. However these are all examples of active restoration – which I am a big fan of – but it’s really hard, small scale and expensive. Active restoration has its own work stream in the plan and is completely different to SMAs. In the Sea Change – Tai Timu Tai Pari marine spatial plan SMAs are Special Management Areas, they are described as “limiting all commercial fishing, and in addition the restrictions would extend to most recreational fishing (with the exception allowing for ‘low volume/high value’ catch)” They were proposed for the Mokohinau and Alderman Islands. Without strong limits on recreational fishing I expect the SMAs would have failed to create conservation outcomes in a similar fashion to Mimiwhangata. The experts have redesigned them as High Protection Areas (HPAs). The experts decided the SMAs (like Rāhui expressed as section 186 closures) are fisheries management tools rather than conservation tools. It will be interesting to see if DOC can get them to meet the International Union for Conservation of Nature’s (IUCN’s) high protections standards. Assuming these are the SMAs NZUA refer to, the SMAs would not have meet their own criteria (as an MPA that they are willing to support) because they would have displaced fishing effort.
By using the wrong terminology and examples, we can see NZUA have not paid much attention to the statements. The uninformed caveats for MPAs they would support show a general lack of awareness of ocean conservation. I hope they clarify their position. It sounds like NZUA and the blood sport groups will oppose the HPAs proposed in Revitalising the Gulf. This is disappointing, without more support NZ will stay in the 1% protection level along with Russia and China. See how marine protection in Aotearoa / New Zealand stands on the international stage in this awesome graphic by NZ Geographic.
NZUA are falling out of step with the New Zealand public and drifting away from their international counterparts who are strong ocean advocates. Divers have a unique view of the underwater world, I believe it comes with a responsibility to take care of it. I wish NZUA were more like PADI who are working to protect 30% of our oceans. SSI are also active in Aotearoa / New Zealand with a no harm Marine Conservation programme.
I hope NZUA one day learn to take the same precautionary care for the health of our oceans that they advocate for in diver safety.
An open letter to the Minister for Oceans and Fisheries.
Hon David Parker Minister for Oceans and Fisheries d.parker@ministers.govt.nz
11 May 2022
Tēnā koe Minister Parker
Pāpaka / Paddle Crabs (Ovalipes catharus) are native to New Zealand. There are 10 commercial fishery areas with nearly all the catch on the East coast of the North Island. The commercial catch has been in decline for two decades with no changes to the Total Allowable Commercial Catch (TACC). The TACC is about ten times larger than the recreational and customary catch. The main fisheries (PAD 1, 2, 3, 7, 8) look like they may have collapsed, the TACC for these fisheries total 590 tonnes, landings in the 2019-20 season were only 19.2 tonnes (3% of the TACC).
I disagree that the fishery is only lightly exploited (FNZ 2021).
Commercial paddle crab landings (tonnes)
Please research the current population. If you don’t have the resources to do this then I recommend you:
Dramatically reduce the TACC for Pāpaka to allow the species to recover.
Reduce the daily bag limit from 50 to 5.
Ban the use of nets in estuaries which kill Pāpaka and other declining species as bycatch.
The response leaves catch limits incredibly high (765 tonnes for commercial) despite acknowledging that commercial take is incredibly low. The minister assumes that the population is healthy but provides no data to justify the decision.
One of the interesting challenges associated with kūtai / mussel reef restoration in the Hauraki Gulf Marine Park (HGMP) is the lack of a reference bed.
The last natural soft sediment kūtai bed left in the HGMP is in an estuary and recovering after being wiped out by a storm in 2015. This means our best reference beds are those under or adjacent to kūtai farms or previously restored. Myself and other divers have helped look for a natural bed in The Noises group of islands which still has old kūtai growing on rocks. On the first of April (to celebrate the tipa / scallop closure which will temporarily protect the seafloor around the Noises from dredging for the first time ever!) I went for a dive / snorkel with Sue Neureuter who wanted to show me kūtai recruiting on shell near the base of some rocks. It was disappointing to see large losses the kūtai growing on the rocks due to a devastating combination of recreational harvest and this summers cyclone impact. The kina barrens were shocking and the area dearly needs protection. However we did find some recruits. The juveniles look very cosey in the old shell showing how dead shell still provides many ecosystem benefits, possibly including a suitable recruitment substrate. There is not much primary recruitment substrate around (kelp) but I did see some beautiful christmas tree hydroids.
Juvenile kūtai growing in adult shell
I was most excited to find a small c4mx4m bed of kūtai growing on soft sediment. I lifted kūtai up at the edge of the bed and they were only attached to each other and some dead shell. I don’t know if the kūtai recruited on to the shell hash here or if they came off the rocks and built up over several years. Some of the kūtai were old and large but most were closer to 9cm long. I did not measure any. I took some photos and spent two minutes doing some photogrammetry on part of the bed using this process I also took a sample of the shell hash.
The bed was remarkable because:
the kūtai sat at a very similar depth in the shell hash compared to softer sediments
the bed was lacking any signs of bio deposits from the kūtai (I have seen this once before at Marsden Point but thought it was just due to really high current which there is not here)
the bed had less colonial epifauna than restored beds
the bed showed no signs of clumping which is a very important feature of established beds
the bed had some young ecklonia radiata growing in it (I should have lifted one up to see what it was attached to)
the portion of the bed I mapped contains some >10 cooks turban suggesting shell is or was swept into the area
Let me know if you notice anything else unusual. If the Noises kūtai were protected and able to regenerate it would help us learn a lot about kūtai restoration.
Movement of larvae has been modelled in the Hauraki Gulf / Tīkapa Moana / Te Moananui-ā-Toi. It’s beautiful to watch and I wish I could share it with you. No matter where the larvae start off they pulse north south with tidal rhythms that make it look like the Gulf is breathing. Depending on the swell, wind direction and currents they drift for 10’s of kilometres in all directions connecting east, west, north and south.
In this video I have tried to visualise what I saw and felt looking at the modelling work. I have used our six tiny marine reserves because they make a disproportionate contribution to breathing life in to the Gulf.
On an ordinary part of our coastline in 1975 our first marine reserve was created. The Cape Rodney-Okakari Point Marine Reserve at Leigh was difficult taking 13 years to overcome all the objections from fishers. 47 years on what have we learnt?
We now know the sacrifices those fishers made has been paid back a hundred fold. The reserve is home to large fish which make a disproportionate contribution to the Gulf Tāmure / Snapper population. It takes thirty six 30cm Tāmure / Snapper to make the same amount of eggs as one 70cm Tāmure / Snapper. Adult Tāmure / Snapper within the reserve at Leigh were estimated to contribute 10.6% of newly settled juveniles to the surrounding 400km2 area, with no decreasing trend up to 40km away. The commercial value of the nursey has been estimated at $1,490,000 per annum. That’s a huge contribution and it makes you wonder how bad things would be without the reserve, what’s worse we might not even know how bad it had gotten.
The marine reserve at Leigh was designed to act as a benchmark, a view of what an unimpacted ecosystem would look like. It’s the best place to experience marine wildlife. The fish are big and abundant, the water is alive and exciting. Putting your head underwater is like looking back in time when the ocean was healthier.
With every passing generation we lose memories of abundance and diversity. When I wonder if I saw more seahorses as a child I can’t be sure. This is the value of having a reference point to measure marine health.
Our marine scientists now understand edge effects, population source & sink dynamics and the connections between geology, habitat and biodiversity. They understand how intact ecosystems are more resilient to pollution and change. At 2,350ha the new Waiheke marine reserve is four times the size of the Leigh marine reserve (547ha). I think it will out perform the Leigh marine reserve and deliver our best chance of experiencing an intact marine ecosystem in the inner Gulf. It could be a benchmark, the gold standard to which we measure other changes we make.
There will be many additional benefits for the Waiheke marine ecosystem like protecting against overfishing and improving the resilience in the face of climate change and pollution. But it’s the reserves function as an experience of unimpacted ecosystem, a window back in time, not just to 1975 but further back before human impact, that’s what we hope to discover.
But this time machine won’t happen without your support. Please visit https://www.doc.govt.nz/waihekeproposal/ and let the decision makers know what excites you about the proposal.
