SOUTH KAIPARA LAKES SURVEY AND DABCHICK CENSUS FOR 25TH APRIL 2019 COMPILED BY DENISE POYNER – JANUARY 2020

It’s a bit late. However, I’m in the head space to write up the 2019 report for the Dabchick Census completed on 25th April 2019.

 38 volunteers  819 wetland  36  Waioneke school  A puzzle or two  Health & Safety children attend again  Update on activities  Atlas

It’s important, I believe, to maintain a sense of what the survey is about and what it entails. This is a scientific survey where at least some insight into the process is provided in each report.

The survey was started in 1969. It is run by the Ornithological Society of (aka Birds New Zealand), and is particular to the Auckland region of this organisation.

The survey is held annually on only one day of the year being 25th April. We do this regardless of the weather. Volunteers who come along are placed in groups with a knowledgeable birding person to help identity the birds they are seeing. At the end of the count we enjoy a barbecue hosted by a local South Head resident and South Kaipara Landcare (SKL).

The volunteer group is a mix of SKL members, Birds NZ members, South Head residents and interested parties. As we have sixteen active sites with water in them, it is great to have a good number of volunteers. On the day we had 38 volunteers attend. This is a great number to have along to help with the count.

We have twenty-five sites in our records. Nine lakes are classified as dry. They are mostly situated in the southern area of the dune lakes system. The dry sites are affected by the water uptake of Woodhill Forest. All lakes remain on our list to visit.

The count covers three things. Firstly, we are counting New Zealand dabchicks and their close relative the Australasian little . We are looking for adults and juveniles of each of these . Secondly, we count other wetland birds such as all species of shags, white-faced heron, Australasian bittern, black swan, Canada geese and feral geese, a variety of ducks, Australasian shoveller, teal and . Finally, we also make note of the presence of any other bird that is related to the wetland area such as pukeko, Australasian harrier, stilts, terns, oystercatchers, and common passerine.

Statistics are generally meaningless unless there is a scientific test supporting research. On the other hand, it is interesting to see how populations of a species can change over time. As this is a New Zealand dabchick census, and we count its close relative the Australasian , I’d like to show you the count from 2013 to 2019 for these two birds.

2013 2014 2015 2016 2017 2018 2019 19 13 14 28 31 33 36

Here’s an update on the graph I placed in the 2018 report.

South Kaipara Lakes Survey - Count of Dabchick 2013 -2019 40 35 30

25 20

15 Number 10 5

0 2013 2014 2015 2016 2017 2018 2019 Year

Back around 2001-2006 the count was around, or over, 100 birds. We saw a big decrease to 53 birds in 2007 and a continuing decrease since then. Countering that though, and while not back to past numbers in the population, it is heartening to see an increase in grebes across 2016 to 2019. Decreases in bird population is a concern. What’s doing that? Several factors can be considered – rainfall, food availability due to habitat changes, pest control or lack thereof, external disturbance such as boats, jet skiers and water skiers, and water quality. External disturbance is an important factor due to the species nesting in a pile of aquatic vegetation on the waterway. (Szabo, 2017).

In the seven years, 2013 to 2019, the overall count of birds takes a bit of a ride. Sometimes it has been around 1000 birds, sometimes well over that at around 1300 birds, and sometimes well under that at 700-850 birds. Mostly though the ups and downs are about the number of water fowl we count. Species like , grey duck, mallard, and mallard x grey duck show fluctuations over time.

Other significant changes over the seven year period of 2013 to 2019 include: a decline in little black shag; a decline in little shag; Canada geese show a lumpy ride across the seven years; an up and down year on year affect on paradise shelduck; a big drop in mallard x grey duck from 2018 to 2019, but otherwise an average, expectable count for 2019; a good year for Australasian shoveler earlier on, but down to 14 individuals in 2019. Generally, most species bobble along as determined by habitat conditions.

Pest control is a big factor in the survival of any species. I am aware South Kaipara Landcare actively engages in pest control activities. Over time this is sure to have good effect on populations of birds. An actively engaged landowner doing pest control has killed 380 pests since he started. The list of pests includes: hedgehogs, rats, stoats, possums, ferrets and feral cats.

The next section is facts about the New Zealand Dabchick. I have reviewed current information, amended references where necessary and included a bit more detail as a result.

Short facts about New Zealand Dabchick

Scientific name: : Podicipediformes Family: Podicipedidae and species: rufopectus

They have been around a long time. G R Gray named them in 1843. (Szabo, 2017) Other names: In Maori, they are called several names. Those names appear to be localised. For example, in the Hokianga they are called taihoropi. In the Waikato, they are known as taratimoho. Other names are weweia and totokipio and . (Szabo, 2017) Description A small to medium sized bird belonging to the grebe family. They are diving birds. Long necked. Can change their buoyancy. Brown-black in colour with a rufous red breast (in breeding season) and yellow eye. White under- feathers including end of the tail. Thick olive-green legs with lobed feet. Feet are yellow on the inner side and edges. Short black bill. (Szabo, 2017) About 29cm in length and 250 grams in weight. (Wikipedia, 2017)

Population, Population and Conservation status: conservation Origin: Endemic (Szabo, 2017) status, threats, Number: 1900 – 2000 individuals. (Szabo, 2017) location, and Conservation Status: Near threatened (Wikipedia, 2019). Recovering behaviour. (Szabo, 2017)

Threats: Predation, water quality, loss of natural habitat caused by wetland drainage, and increased disturbance such as boat usage, jet skiing and water skiing are all threats. Nests are affected by disturbance.

Location: The species inhabits freshwater lakes and ponds on the volcanic plateau, Rotorua lakes area, Northland, Hawkes Bay and Wairarapa. The species could be found in the during the 1800’s and 1900’s. It became extinct as a breeding species in the 1940’s. The good news is a breeding pair was located near Takaka in 2012, and a pair have bred near Blenheim in 2015.

They favour shallow water with dense vegetation on small freshwater lakes and pond, sand dune lakes and lagoons, and larger inland lakes with shallow, sheltered inlets up to the size of Lake Taupo. They will live at sea level and up to 740m altitude. (Szabo, 2017)

For 2019, the strongholds for the species were: Marie Neverman Reserve, Lake Kereta.

Behaviour: The species can change its buoyancy by changing the angle its feathers are held against its body. They can be aggressive toward intruders. The behaviour is displayed as: head being lowered forward, neck and back arched, half raised wings, short rushes or low pattering flight towards an intruder.

Appeasement displays include: head bobbing up and down, side to side and back and forth. They dive as a last resort to escape. They will turn “stern- on and raise and fluff up the rear feathers to display a white “owl-face” pattern on each side of the tail feathers. This is thought to be a territorial behaviour that conveys mild alarm when threatened.

They fly at night. They can cross large bodies of water such as Cook Strait.

Genetically they are a super-species to the hoary-headed grebe of and appear to be related to the of South America. (Szabo, 2017)

Breeding: All year round with territorial displays in June-July and egg laying in the August to February period. Nests are made of aquatic material about 1m deep in construction. They will also build nests in a cave.

Courtship involves: preening, rearing, head turning and shaking, and ritualised displays of diving and pattering.

The species is monogamous. Lay 2-3 bluish eggs that become stained brown in the nest. Incubation is over 22 or 23 days.

Chicks are born with irregular black-brown horizontal stripes on a white background. They have a bright red bill with black markings. Chicks are reared over 70 days. They ride on the parents back for the first week, and mostly over the second and third week until they are too big to do so in the fourth week. (Szabo, 2017).

Chicks are capable of moving around straight after hatching (precocial). They are flightless for the first few weeks but are capable of swimming and diving. (Wikipedia, 2019) Food: Aquatic invertebrates such as insects and larvae, fish and crayfish, shellfish, leeches. (Szabo, 2017)

Waioneke School

A small group of Waioneke School children attended again. A message from Claire Bennett the day after the count gave thanks to Ian and Trina (Birds New Zealand – Auckland Branch) for the great educational activity the children had. Going by the pictures they had a great morning out. We positioned them at the Marie Neverman Reserve as it gives the children an opportunity to engage in some real-life observation and counting. Here are photos of that day.

You might be wondering what activity the children are doing with the clipboards and pens. An exercise to name a dozen birds around the South Head Peninsula was put together. Do you want to try? Here is the exercise. The idea is to name birds properly. Not just that it is a shag, but can you say what kind of shag? Answers are at the end of the report.

In previous reports I have provided information on a species we recorded on the day. I’ll tell you a little story.

On the day, an inexperienced team was allocated to the last dune lake on Wilson Road. Armed with zero in books to look anything up and only their binoculars, they came across a bird they had not seen before. The members of this team got it there were adult Australasian little grebe present. This was a treat as I had not heard of, or seen this species on this dune lake before. There was one individual that was not quite the same as all the other grebes on the lake. They knew what a dabchick looked like. They could clearly determine that the mystery bird was neither a dabchick adult or chick, and was not an adult Australasian little grebe. What to do about this mystery bird?

Three days later back went one of the team members along with someone that might know. Alas their count of five grebe was four. They could not see the individual that was there on the day. I went out seven days after that trip armed with my camera. There were 5 back again. I took photos, hummed and aahed about it thinking that it was a grebe, but what.

The photos were sent to our Birds New Zealand Regional representative, Ian McLean. He took a good guess at it and forwarded the photos to Colin Miskelly whom takes care of the NZ Birds Online website. Colin was able to identify it as a juvenile Australasian little grebe. They are not often seen. Back in 2001 fifteen were sighted. In 2002, nil were sighted. Then there is a run of 2, 3 and five and then none for a few years. They next pop up in 2010 with a count of 3. Then there is a big gap when one was sighted at the Green Lake in 2018. In 2019 five juveniles were sighted. This supposed 6th one can not be confirmed as being the mystery bird, however, I think we solved the puzzle. Roll on next year to see what comes up.

Below, is a photo of the juvenile bird taken on Wilson Road, April 2019.

For this year, the species of the day is the Australasian little grebe. Here are some short facts.

Scientific name: Order: Podicipediformes Family: Podicipedidae Genus and species: novaehollandiae (Wikipedia, 2019)

The species is a recent arrival. It has come from Australia. Breeding started in Diamond Lake near Wanaka in 1977. (Szabo 2013; updated 2015)

Other names: Eastern little grebe, , Australian grebe. (Szabo, 2013; upated 2015)

Little grebe, tricoloured grebe. (Scofield and Stephenson, 2013)

There is no Maori name that I could find.

Description: A small to medium sized aquatic diving bird with a length of 23-27 cm long, and a weight of 100-230 grams. They have large powerful lobed feet that are set far back on the body. This helps them to propel and steer themselves in the water. They do not walk well on land.

Both sexes look alike. The male is slightly heavier. Like other grebes, the young chicks have white striped markings, red-pink eye ring and a pinkish- yellow bill with brown markings. The striped markings are present on the head and neck until adult plumage develops. The bill will turn black. (Szabo, 2013; updated 2015)

Population and Population and Conservation status: conservation There is no current information to advise the current number in New status, threats, Zealand. In 1995 it was estimated there were 50 individuals. locations and behaviour: Globally, the population is estimated at 25,000 to 1 million birds. The conservation is classified as “Least Concern”. There is no active conservation effort of the species. They are abundant in Australia.

Threats: The species lives on small water bodies. Small water bodies can be susceptible to drying up.

Location: Since 1977, the species has held populations in Northland, Rotorua Lakes area and Canterbury. There has been a notable increase in Northland and Auckland areas. The species appears to have died out in the South Island with no sightings since 2008. This has been attributed to the drying up of waterways caused by reduced ground water levels in parts of Canterbury.

Behaviour: Australasian little grebe live on freshwater lakes, sand dune lakes and farm ponds. They are seen in pairs. It can change its buoyancy by adjusting the angle it holds its feathers against its body. This allows them to swim high or low in the water, and to dive frequently. When alarmed they can sink below the surface. Their long neck and head gives them a “periscope”. It can put its head and neck under the surface as if it was snorkelling. They do this when searching for prey.

They can be aggressive towards intruders. They have an attacking upright posture with the neck held erect, ruffled feathers and tail tuft cocked. They will kick water and splash-dive. Displays of appeasement include holding the head and bill low in the water with the neck slightly forward and the rear under water.

Pellets of small feathers are formed to help combat gastric parasites.

They fly at night. (Szabo, 2013; updated 2015).

Breeding: In breeding plumage, they are an attractive bird with a glossy black head and neck. There is a red (rufous) colour around the face. They have bright yellow eyes, and a yellow gape patch at the base of a short, black pointed bill. The legs are grey-black with large lobed toes.

When in non-breeding plumage, their colouration is grey-brown above, paler grey-white below and the rufous coloured plumage is not present. The yellow gape is not present after breeding. The tail is a short, pointed tuft of dark feathers.

In New Zealand, the egg laying period is from January to April. They form solitary pairs on freshwater lakes, dune lakes, and farm ponds. The nest is anchored to aquatic vegetation. The pile of vegetation is about 60 cm deep.

They have a courtship display including: parallel swimming, forward or hunched displays on the water, similar displays on the nest platform and trilling. The nest contains 4 bluish eggs. The eggs will stain a reddish-brown colour while in the nest. The incubation period is 23 days. Chicks are raised over 8 weeks and is shared between parents. The chicks ride on the back of a parent until they gain independence. (Szabo, 2013; updated 2015)

Food: Likely to eat small fish, snails and aquatic insects caught during diving behaviour, vegetation and small frogs. (Szabo, 2013; updated 2015)

Other grebe species:

As well as the two grebe species noted in this report, we do see two other of the grebe species in New Zealand. If you would like to read up on these two species, please go to www.birdsonline.org.nz and use the search engine field to find information about the species.

Hoary-headed grebe

We do have hoary-headed grebe in New Zealand from time to time. They are a native vagrant coming to us from Australia.

Australasian crested grebe

There is a good sized population of 600 birds found in the South Island in places like Te Anau, Twizel, and Lake Elterwater.

Health & Safety Increasingly, workplaces and volunteer organisations are required to commit to health and safety practices. Back in April last year, I received a comprehensive set of information covering the Health & Safety Policy for Birds New Zealand (the National organisation), Guidelines for Field Trips, and a list of potential hazards and risks.

Team leaders are appointed from Birds New Zealand Auckland branch members. They will have the responsibility of undertaking a site risk assessment on the day. If you volunteer on the day, we will record your name for the team you are in.

Closer to 25th April 2019, I will sort out better how to manage this. Please at least expect to hear a safety briefing before we depart to site, and to have your name noted on our Health and Safety documentation.

Bird Atlas Some residents may be aware of a Bird Atlas scheme. At the June AGM for South Kaipara Landcare, this tool for recording birds was mentioned. We went on to have a day of learning about this and to have a hands-on experience at recording for the Bird Atlas. This is a five-year scheme of updating our birds nationwide.

I alluded to the fact that the Bird Atlas is important to Birds New Zealand, however, it can not be incorporated into the Dabchick Census. If you have an interest in recording all the birds sighted at the site you go to on 25th April, you are most welcome to do so. This is your own endeavour. I am happy to help anyone interested in learning how to do this.

Other related activity November 2018 – On a three-yearly basis, a group visits the dune lakes at the back of the Otakanini Topu property. This was done by Denise Poyner, Greg Smith and Helen Smith. Sadly, many of the lakes near the Woodhill Forest boundary were found to be mostly dried up and a lot of tobacco weed present. We did have a good sighting of white-faced heron from the visit. The next visit will be in 2021.

Reports of dabchick chicks – earlier in 2019, I had checked on the presence of dabchick chicks in the area where it was most likely to occur. Glad to say I heard of two chicks on the peninsula.

References: Szabo, M.J. 2013 [updated 2017]. New Zealand dabchick. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz . Accessed 27th January 2020.

Szabo, M.J. 2013 [updated 2015]. Australasian little grebe. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz. Accessed 19th January 2020.

Wikipedia. 2019. Australasian grebe. en.wikipedia.org/wiki/Australasian_grebe. Accessed 19th January 2019.

Scofield, R. Paul and Stephenson, B (2013). – a photographic guide. Auckland University Press, Auckland, New Zealand.

Photo Credits: Smith, Roger. 2017. New Zealand Dabchick carrying chick on its back. Photo taken at Waikanae Lagoons. www.nzbirdsonline.org.nz . Accessed 13 August 2017.

Bennett, Claire. 2019. Photos of Waioneke School children at Marie Neverman Reserve.

Smith, Trina. 2019. Photos of Waioneke School children at Marie Neverman Reserve.

Poyner, D.M. 2019. Photos of twelve local species.

Poyner, D.M. 2019. Australasian little grebe. Juvenile. Wilson Road, South Kaipara Head. May 2019. In Miskelly, C.M. New Zealand Birds Online. www.nzbirdsonline.org.nz. Brooks, S. 2019. Australasian little grebe. Adult. Tikipunga, Whangarei. October 2019. In Miskelly, C.M. New Zealand Birds Online. www.nzbirdsonline.org.nz.

Brooks, S. 2019. Australasian little grebe. Adult calling just after laying egg on floating nest. Tikipunga, Whangarei. October 2019. In Miskelly, C.M. New Zealand Birds Online. www.nzbirdsonline.org.nz.

Feasey, L. 2018. Hoary-headed grebe. Adult in breeding plumage. Lake Elterwater. September 2018.

McKenzie, C. 2010. Australasian crested grebe. Adult. Lake Dunstan, Central Otago. January 2010.

Quizz Answers: Reading left to right:

First Row – Tūī, little shag, white-faced heron Second Row – New Zealand dabchick, white-fronted tern, Australasian bittern Third Row – Grey teal, pied shag, Australasian shoveler Fourth Row – Scaup, , Australasian harrier.