Northern New Zealand dotterel productivity rates

Northern New Zealand dotterel are classified as a Conservation Dependent species, this means that without human help they will go extinct (usually because of predation from introduced predators like rats & cats). So how do you know if your local dotterel are going extinct or not?

Well first you need to work out their productivity rate. Productivity is measured by the average number of chicks fledged per breeding pair (per season). Chicks divided by adults. So if you had two pairs and they fledged one chick you can say the site averaged half a chick (0.5) per pair.

Management is considered effective if productivity values are greater than 0.5 for three consecutive years or longer (Dowding & Davis, 2007).

I help manage dotterel at three sites, I can not claim effective management and any of them. This means that over time these sites are a population sink. It’s important to track and share this metric to help conserve the species.

Tarāpunga / red-billed gulls nest extension

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.

Missing reef balls

24 Reef balls were deployed in two reefs at Long Bay-Okura Marine Reserve in 2001.

Launching the reef balls, photo care of Jonathan Jaffrey

They were quickly colonised and dramatically increased the biodiversity in the area.

A lonely reef ball, photo care of Jonathan Jaffrey.

I have wanted to find these artificial reefs for years and made three attempts. The first dive from the shore was unsuccessful (its too far out and I dont have underwater GPS). The second and third efforts below used line and sonar but still came up empty. I think they have been buried (sunk into the substrate) but I would love to be wrong. The photo above shows a lot more shell on the seafloor than I found 20 years later. I’m not planning any future searches.


12 January 2022
4:15pm High Tide
5-10 knots
.5m-1m swell
Shaun Lee & Jordi Tablada

Boat to from Winstons Cove to Long Bay
12:00pm Look for Reef Balls:

Zig Zag Reef
36° 40’ 52” S, 174° 45’ 14.8” E
36.681111, 174.754111
5.5m at Low tide

Octagon Reef
36° 40’ 51.1” S, 174° 45’ 19.6” E
36.680861, 174.755444
6.2 M at low tide

Dropped anchor 5m from Zig Zag using Garmin GPS
Dived down anchor with line on reel
Vis 5m surface, <1m bottom 5.5m deep, tied line around anchor, spiral search pattern Let line out >30m possibly didn’t turn enough and made more of a sweeping arc
Hoped line would have snagged of epibenthic fauna attached to reef balls but following line back found nothing
Quick check near boat found nothing c30mins total bottom time
Noted layer of mud under sand
A few cushion stars, some heart urchins, Jordi saw a Spengler’s Trumpet
Some dead tutua shells under sand
Large snapper under us when we surfaced

Dropped anchor 5m from Octagon using Garmin GPS
7 minute look in the direction of the reef
Nothing in particular

2:30pm head back as wind pickup up (15knots developing in afternoon).

Resolved to search with a boat that has sonar / fish finder next time.


Thursday 9 September 2022
High Tide 5:30pm
With skipper Ed Chignell

Zig Zag Reef 6.7m
2:45pm
c7 spirals out from waypoint. No clear benthic structure seen on downscan or sidescan.

Octagon Reef 8m
3:10pm
c3 spirals out from waypoint. Drifted south over fishy looking shape 5m south of the waypoint on the downscan. It was still there 5 minutes later so we dropped anchor on it.

I descended the anchor line. Vis 3m, bottom 8.8m. I spiralled out from the anchor for 5 minutes then headed north for an additional 5 minutes. The seafloor was sand/mud with some shell. Nine cushion stars and about six large hermit crabs were seen in 10 minutes. After ascending and heading a bit further south I dropped down for another 5 minutes to check out another fishy shape but didn’t see any reef balls or fish. Many fish were seen in the fish finder.

Note visibility much better than last dive even tho it rained heavily just a few days ago. Hardly any swell or wind over the last two days.

UPDATE: WE FOUND THEM!

https://inaturalist.nz/journal/shaun-lee/74488-dive-report-reef-balls-long-bay

Article about the find here https://gulfjournal.org.nz/2023/02/reef-balls-rediscovered/

Thanks to Andreas Proesl who has been in touch and supplied his internship report which shows how the ReefBalls were constructed and deployed

Photo kickstarts stream restoration

I recently had a great experience with Waikato Regional Council (WRC) which showed the value of just letting council know whats happening.

I was driving past  270 Kuaotunu, Wharekaho in the Coromandel and saw cattle defecating in the stream. I was in a hurry but decided to take a quick photo and reported it a few days later. I got a great response from WRC. The land is owned by the crown, managed by Thames-Coromandel District Council (TCDC) and leased to a farmer. The stream is a priority one waterway given it’s proximity to the coastal marine area which cannot have stock access without a resource consent.

Staff discussed the issue and the farmer running cattle on the property will now remove cattle from the land. TCDC envisage releasing the tenure to the Department of Conservation who may review activities at the site and consider restoring it. What a great outcome! I am very impressed with all agencies involved.

Careless statements from NZUA

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.

Most divers and the New Zealand public understand this, which is why marine reserves are so popular. There is 77% support for 30% marine protection in the Hauraki Gulf Marine Park and 93% of the submissions for a recent marine reserve proposal for Waiheke Island were supportive, despite opposition from the blood sport lobby groups.

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 Plan and 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.

Pāpaka

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:

  1. Dramatically reduce the TACC for Pāpaka to allow the species to recover.
  2. Reduce the daily bag limit from 50 to 5.
  3. Ban the use of nets in estuaries which kill Pāpaka and other declining species as bycatch.

Thank you

References

FNZ 2021. PADDLE CRABS (PAD) https://fs.fish.govt.nz/Doc/25060/55%20PAD%202021.pdf.ashx

UPDATE 19 August

Response from Hon David Parker.

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.