The Red Beak District

THE RED BEAK DISTRICT 

PROMISCUOUS PUKEKOS

Forget 'Fort St' in Auckland or 'Kings Cross' in Sydney, there are far more sinister districts popping up all over the place at this time of year. From August to March every year New Zealand's recreational parks and open fields are transformed into 'Red beak districts' where promiscuity and 'fowl play' is the name of the game!

Pukekos (Porphyrio porphyrio) would have to be the hippies of the avian world, a world that consists of 'free love' and communal living! Group sex, partner sharing, homosexuality and incest are a common occurrence. In fact, in the pukeko world you could say that love is one big 'family affair'.  (Right: No privacy in a pukeko commune)

Pukeko's have a complex social system, and monogamy, polygamy, polyandry,  and polygynandry can occur  within the same population! Females are often hounded by numerous males and can be copulated by up to three different males within a matter of minutes! (Below:  Males hastily pursue an unwilling female)

This kind of libertine lifestyle raises a lot of questions... how could this level of promiscuity benefit the pukeko? Partner sharing seems to go against the evolutionary grain, where it is argued that as a result of natural selection individuals will try and maximize their own genotype in subsequent generations. Although in communal breeding groups it seems that they toss their own interests aside in order to assist the reproductive efforts of others and benefit the group as a whole.

There are many theories as to why these purple clad hippies share mates and participate in incestuous and homosexual activity when it seems detrimental and pointless to their evolutionary success.

When it comes to inbreeding it seems that pukeko have several mechanisms for reducing the disadvantages of incest such as possible gamete selection (the process of determining which egg matures and what sperm succeeds in fertilizing the egg). Other theories suggest that regular inbreeding may have eliminated deleterious generic consequences. Whatever the reason or reasons may be, there have been no obvious harmful effects due to inbreeding observed in pukeko breeding groups. Homosexuality and partner sharing are believed to help synchronize sexual cycles allowing several females to lay in the same nest at the same time.

Although these raunchy rails' sexual habits may seem a little lewd and communal breeding an evolutionary paradox, these districts, believe it or not, are 'family friendly'. In fact these lewd acts seem to benefit the group as a whole, and strengthen family ties. Community breeding offers its fair share of advantages, such as safety in numbers as each 'commune' has several males to defend it. It certainly makes the jobs of nestbuilding (Below), chick feeding/care (Right) and incubation (which is shared by all adults within a group) a bit easier with more helpers around. Due to the fact that males and females mate freely within the group, males have an uncertainty about which chicks they've fathered and this probably ensures that they  stick around and help with the raising of the chicks.

Each female will lay up to 7 eggs, and a communal nest can have eggs from 2-3 females. Unaware of the pukekos communal nesting behaviour early ornithologists were fooled into thinking that some females were highly productive because their nests contained up to 20 eggs. With multiple chick minders each chick may be looked after  by a parent, aunt/uncle or an older brother/sister.
 

Left: Males and females both participate in nest building, and in communal breeding groups helpers also lend a hand (or a beak).

 

Right: allopreening. In pukekos, allofeeding and allopreening (where birds will feed and preen one another) is a form of courtship and occurs between all sexually active birds in a group. Male pukeko also hold water weeds in their bill and bow to the female with loud chuckles as a form of courtship. 

 

Left: A pukeko swimming. Although not web-footed, pukekos are surprisingly strong swimmers.

Below: A pukeko nest  situated in an open field.

Pikitia 2010 postcard range

The NEW Pikitia postcard range is available NOW...      www.pikitia.co.nz 

Pikitia is a small but growing postcard company based in Tauranga New Zealand. Pikitia have just starting selling in Rotorua one of New Zealand's tourist hot spots (no pun intended). They have recently put out a new postcard range (2010 range) in which my photos (above) are included. Pikitia has some beautiful New Zealand images ... check them out at - www.pikitia.co.nz

SPOTLIGHT: White-faced heron (Ardea novaehollandiae)

White-faced herons would have to be one of my favourite birds to photograph! (I tend to say that about a lot of birds). Although there aren’t too many birds that can rival the beauty, grace and finesse of the heron, or match the heron’s speed, precision and deadly accuracy. I never seem to tire of watching the herons feed at my local estuary, herons are masterful hunters, and I've seldom seen a heron miss its target. In the above photo a small mud crab hangs onto the heron's beak for dear life!

DISTRIBUTION: The white-faced heron is common throughout most of Australasia, and was self-introduced to New Zealand in the early 20^th century. It was first observed breeding here in the 1940s and now breeds in abundance throughout New Zealand.

White-faced herons are very adaptable birds and are particularly successful in New Zealand due to their ability to inhabit almost any wetland environment, from sandy/rocky shores, estuaries, mudflats, lakes, rivers, pastures … in fact white-faced herons are just at home inland as they are on the coast. 

  

DIET & FEEDING: White-faced herons are now the most common heron species in New Zealand; part of the reason for this success is their varied diet which consists of molluscs, insects and their larvae, spiders, plant matter, small fish and reptiles, frogs, marine worms and even mice. 

White-faced herons stalk their prey by either actively wading in shallow water or standing still and waiting for prey movement. White-faced herons use an assortment of techniques in their feeding repertoire from wing flicking and foot stirring (both used to disturb and subsequently locate small fish and invertebrates) to chasing prey with open wings.

For such an elegant bird the white-faced heron's call has been described as a 'croak', 'gobble' or gutteral "grraaw", which is typically given in flight or during aggressive encounters.

Prior to the breeding season the herons undergo a moult and as a result develop reddish-brown nuptial plumes (breeding plumes) which appear on the foreneck & breast and long blueish-grey plumes on their back. The nuptial plumage is brighter than their basic plumage, for the purposes of sexual display.

BREEDING: The breeding season peaks between October and December where usually 3-5 eggs are laid in a messy nest of sticks high up in a tree. For around 25 days both the male and the female will share incubation duties. Chicks hatch with a white down and will fledge after approximately 6 weeks. The young stay with their parents until the next breeding season. 

So next time you're out and about, keep an ear out for that unmistakable "graaww" and spare a thought for these wonderful birds... chances are there's one near you!


A reef heron (Egretta sacra) stalks its prey in a typical hunched pose in the photo below. Reef herons are a much less common sight here in New Zealand. 

 

Garden bird survey 2010

This year Landcare Research in association with Forest & Bird and the Ornithological Society of NZ ran its 4th National Garden bird survey. This year has been the most successful survey to date, with approximately 4000 participants, twice as many as last year! 

The survey was created to find out more about the population dynamics of native bird species in our towns and cities, something we know virtually nothing about. The survey takes place in mid-winter every year, when native birds are more likely to visit our towns and cities in greater numbers. The survey took place between the 26th of June and the 4th of July where all willing participants spent an hour recording the highest number of each bird species they saw at one time (birds heard and seen flying overhead were also recorded). 

Although its still early days to show any real long term population trends, there have been some interesting results based on the 4 surveys conducted to date.

Top 10 garden birds compared (2009/2010)

House sparrows & silvereyes have been found to be by far the most common birds visiting our gardens throughout the country; with house sparrows being more common in people's gardens in the north of the country and silvereyes being much more common in the south. Interestingly, silvereyes were more common than house sparrows in 2007 (with an average of 10.2 silvereyes compared to an average of 9.4 house sparrows), while for the last 2 years house sparrows have been the most common garden species due to silvereye numbers crashing, especially in Otago and Southland (Avian pox is thought to have been the culprit, with several people in Dunedin noticing silvereyes with growths around the bill, eyes and legs). This year however results so far have shown silvereyes make a come-back and regain the top spot as the nation's most common garden bird! (See table above)

 
Other results have shown some exciting visitors to our gardens. Stitchbirds have been recorded in gardens in Auckland and Wellington, close to areas where birds have been introduced like the Waitakere Ranges and Karori Wildlife Sanctuary.

Red-crowned parakeets (Kakariki) were reported in an urban garden in Torbay (15km from Tiritiri Matangi Island) and in a garden in Glenfield (25km from Tiritiri). Some people have also recorded seeing Kaka come into their gardens and feed from feeders.

To see progress results of the 2010 survey as they are entered into the computer please click here 
http://gardenbirdsurvey.landcareresearch.co.nz/SpeciesTotals.aspx

SPOTLIGHT: Grey Teal (Anas gibberifrons)

Often described as plain in colour, I think the grey teal is a beautiful bird, with their mottled brown scalloped plumage, subtle shape and stunning red eye. Here in New Zealand the grey teal has a wonderful success story...

The grey teal (Tete) are probably one of the less thought of birds here in New Zealand, these small ducks are often overshadowed by their rare cousins, the Campbell Island teal (critically endangered), the Auckland Island teal, and North & South Island brown teal.

In fact the grey teal was once itself a rare sight in New Zealand, and R.H.D Stidolph in a 1945 article in the 'Emu', an Ornithological Journal, states his delight in sighting the grey teal..."It has been my good fortune to come across the Grey Teal in three different localities in the Wellington district in the last 14 years...". R.H.D Stidolph also states "The grey teal in New Zealand has always been regarded as a rare bird". I can just imagine Stidolph's jubilation if he were to take a stroll down at the oxidation ponds here in Christchurch and see teal in their hundreds!

 
The 1950's saw an influx of grey teal into New Zealand due to drought in Australia. Grey teal are nomadic and will often travel great distances to colonise suitable habitat following rain. In an Australian study grey teal were recorded covering up to 343km within hours to occupy a new site and were shown to travel over 2000km in a single year! Since the 1950's the population of grey teal has increased, with more than 50,000 birds being recorded here in 2005.



Grey Teal are now considered a common native and thankfully are protected here in New Zealand and subsequently not hunted as they are in Australia.

The photo on the left shows a grey teal typically dabbling (filtering surface water or mud through their bill) for seed and small insects. Other feeding techniques include grazing on plant material from overhanging plants and upending and feeding from the bottom.

 
Grey teals prefer to build their nests in tree hollows, although will nest on the ground in a shallow bowl of grass often in the cover of reeds. Six to nine cream coloured eggs are laid and gradually covered in down, the eggs are then incubated by the female for approximately 25 days.

Lets hope that someday New Zealand's other native teal species will follow in the same footsteps as the grey teal, and the oxidation ponds here in Christchurch will be teaming with South Island brown teal!!!