Päiväkirja-arkisto kohteelle helmikuu 2022

16. helmikuuta 2022

Notes on Brown-hooded Kingfisher

Notes on Brown-hooded Kingfishers Breeding Prey and Behavior
Van Kervel Dam, Garden Route Botanical Garden

During December 2020, a partial record of what a pair of Brown-hooded Kingfishers brought to chicks was made when the paid were regularly seen at the same place carrying food items. Repeated splash bathing by at pair of birds had initially brought it to attention to the spot. Nd a chai.Initially, both birds were very wary and would not go into the nesting burrow if any people were in the area, but very quickly became tolerant of people, the female more so than the male. A hide was impractical due to very limited space between a well-used path and the water’s edge. Feeding activity was observed from 3rd December to 26th December 2020 and photographed in a limited manner. The male was never seen feeding the female although it is possible. Chicks were never seen. For species list and totals, seen the table below.
In October 2021, repeated splash bathing by a pair of kingfishers near the same spot regularly, gave rise to suspicions that a new nesting burrow had been excavated some 10m from the one used the previous year. When the male was seen feeding the female at this spot, suspicions were confirmed. A decision was made to spend as much time as possible monitoring the site, recording the catches and behaviour, without building a hide The photographer/observer could sit, only partially hidden by vegetation, just off the footpath, without disturbing the birds at all. Basic equipment consisted of a camera, a chair. The birds very quickly accepted the strange human on a chair as just another part of the environment but did become agitated or flew away when others stopped, particularly if there were more than two other people.

The nest sites 2020 and 2021 have the following similarities:
Burrow in a vertical earth wall, about 1m below the path level, well above maximum dam water level.
A dead tree, fallen almost horizontally, in front of the burrow entrance. This is used by the male feeding the female (food is transferred on this perch) and by both adults who land here before entering the burrow, male lands here before when leaving the burrow after feeding chicks, female so occasionally.
A standing dead tree nearby from which the male calls to the female particularly during the period the female is brooding and he is feeding her.
There are distinct physical differences between the male and female birds:
Female is noticeably larger than the male.
Female has a darker brown head, lighter brown back and a more heavily streaked breast than the male.

There are also differences in their behaviour and habits.
Only the female goes into the burrow to brood.
During, and up until the first egg hatches, the male feeds the female. He was never seen entering the nesting burrow until, presumably, the first chick hatched, when he started carrying in food.
The male is noticeably more cautious about entering the burrow carrying a food item than the female is.

At the start of the period when the female started carrying food into the burrow, she always flew away directly from the burrow entrance. The male always perched for a time, looking around, before flying off. As time progressed, the female did start to land on the perch after feeding the chicks, looking around while fluffing up her feathers and giving her beak a good wipe, before flying off. Both bird’s beaks often were muddy, presumably while catching prey on the ground,
Both birds habitually used the same place on the on dead tree in front of the burrow, so much so that the bird could be sexed by where it landed.
For some unknown reason, the male, and only the male, was ever see taking splash baths.
The feeding routine becomes very routine, very predictable. Note that all prey is carried to the nest head first for ease of swallowing, both when the male was feeding the female and when both birds were feeding chicks in the burrow. In most cases, the prey was dead or at least stunned, before arriving at the site.
There was a set routine, seldom varied when the male feeds the female. The male calls to the female from high in a tree some 10m away, the female flies out, onto the perches in front of the burrow, the male swoops steeply down from his perch, flying flow and fast over the water before swooping up to his perch. She must have good hearing to hear his call from at least 10m away while in a burrow probably 1m deep above the road traffic noise close by. Both birds shuffle and hop towards other, the actual food hand over is very quick. A catch was never dropped by either bird in the process. The male flies off almost immediately, female eats food and flies directly back into the burrow after a shake of the feathers and a stretch, regularly making a deposit first. Occasionally the female takes a short flight, never away from the burrow for more than 10 minutes, perching briefly before flying into the burrow.
On rare occasions when the male arrives with food while the female is out, he ate the food item but after a long time.

Observations were made, when possible, from 0700 to around 1200 daily, with the occasional essential “body break” for the observer during these times , many other catches must have been missed and the afternoon were unobserved.

A surprise mating witnessed, 13 days since food was first seen being passed to the female near the burrow entrance. The male called to the female from his usual calling perch, without catch. The female came out, they shuffled towards each other, he mounted her very briefly before they both flew off. Not sure if actual mating did occur, but the intent was certainly there and she was willing. Both birds flicked wings at each other before the mating took place, very brief horizontal partial wing extensions, very different from the territorial extensions when trespassers were repelled.

Day 13, male arrived with food, called for the female, who was out at the time. He flew towards the burrow several times, but did not appear to enter the burrow, returning to the perch each time, calling again. An obviously agitated male then ate the food himself, took a couple of splash dips in the dam and had a quick preen before flying off.

Day 13, suddenly the “calling tree” had 4 kingfishers on it, obviously not friends, much wing flashing, much calling, much hopping about. Main flasher was the resident male, still wet from a recent bath, supported by the female, who had just missed a meal due to her flying around. Two birds flew away, both the resident pair immediately flew down towards the burrow. The female entered burrow, she had been off nest for a while. The male stayed “on guard”, alert and agitated for while before flying off.

4th November: The male gave the female a fairly large Knysna Dwarf Chameleon, head first as usual. She changed grip on the chameleon, grasping it by the tail and bashing several times against the perch, before again turning it around and swallowing it head first as usual. This is the only catch seen that the female had to “treat” before swallowing. Not once out of the 100 transfers seen was a catch dropped by either bird.

11th November, 21 days since the male was first seen feeding the female, an abrupt, distinct change in behaviour of the male who now carries food himself into the burrow. He no longer calls as much from his old calling tree, but swoops in fast and low over the water, from any direction landing on the perch there. He initially made several aborted trips into the burrow, returning to both “chomp” and bash the prey item, some reduced to an unrecognisable pulp, before finally managing to feed the (presumed?) newly hatched chick. The amount of “food preparations” decreased rapidly over the coming days. The male had a set routine, landing at almost the same spot ever time, hopping forward to a branch with a clear flight path to the burrow, spends some time before going into the burrow looking around and does the same before flying off again. Just twice since the male started going into the burrow with food, did he feed the female,

On 14th November, the first time that the female was seen carrying a prey into the burrow herself. Since the male started entering the burrow, the female has been spending amounts of time out of the burrow, returning from a tip empty beaked. She still spends periods in the burrow, the male is only in the burrow for as long as it takes to feed the chicks. She comes in fast and low from any direction, mostly lands in a twig cluttered part of the tree, spends minimum time there before flying and obstacle course to the burrow entrance. She usually flies off directly out of the burrow, does not usually perch again as the male does. Not a bird trained for photography, but also makes it difficult to record all her catches. Gradually her behaviour changed and she did spend more time displaying her catch before flying towards the burrow and started landing on the perch before flying off.

17th November, female was seen flying from the direction of the burrow entrance carrying an egg, an almost intact egg, not the remains of egg shells after a chick hatches. She proceeded to “chop and bash” the egg, revealing what thought to be an almost full term chick, but apparently dead. The female dropped the chick into the water (accidently?) or was she trying to eat her own now dead chick? After this incident, the female did continue to spend time in the burrow, but for rapidly decreasing periods.

17th November to 5th December, routine ferrying in of food items, subtle changes in behaviour, the female now also rests on the perch outside the burrow before flying off, time both parent wait outside the burrow before going in decreasing. Chicks and parents survived a local flood event when over 150mm of rain within 24 hours was recorded. The feeding visit frequency was highly variable, from minutes to over an hour between visits. Prey items seem to be affected by weather and time of the day.

As can be seen from above, these birds will catch and eat just about any animal they can.
6th December, another flooding rain, site not visited due to flooded roads.

7th December, late start, but there was no activity at the burrow.
From Etienne De Beer; Chick seen was flying off followed by both parents, 1 photograph of the chick taken. Around 0800 on Tuesday 7th December.

From “gut feel” interpretation of the parents behaviour, which did become more relaxed during the last few days of feeding and they called for increasingly long periods before taking the food into the burrow, as if they were trying to encourage the chicks to leave the nest.

Time line
21st October 2021 to 11 November (21 days): Male feeding the female. Female was incubating eggs.
11th November 2021 to 14th November 2021 (3 days): Male carrying food into the burrow, female leaving the burrow for increasingly longer periods, but not carrying food into the burrow, probably feeding herself but still incubating eggs.
14th November to 7th December (23 days), both parents bringing food to the burrow, no eggs being incubated.
14th December, both parents with 1 immature seen perched near each other at the near the burrow. Immature was a noticeably a duller blue as they flew away over the dam.

The full catch list, photographed and identified where possible is below. Data extracted from projects on inaturalist. As can be seen, crickets (Orthoptera) (325 catches)) are numerically the most, followed by reptiles (124 catches). Although invertebrate catches are the most numerous, the vertebrate catches are, on average, significantly larger and make up a very significant part of the diet by weight. A surprisingly large number of Short-legged Seps were caught, an animal seldom seen in the area.

Colin Ralston
December 2021


Brown-hooded Kingfisher catch list
A B C D E

Scientific Name Common Name Count Count Count Count Totals B+C+D Totals A+E
Gryllidae True Crickets 42 35 38 70 143 185
Gryllotalpa Mole Crickets 13 24 44 35 103 116
Tetradactylus seps Short-legged Seps 31 11 16 26 53 84
Bradypodion damaranum Knysna Dwarf Chameleon 7 5 11 16 23
Gryllidea Crickets 5 10 6 1 17 22
Hyperolius marmoratus Spotted Painted Reedfrog 7 1 6 5 12 19
Lygodactylus capensis Common Dwarf Gecko 1 3 2 9 14 15
Potamonautes barbarai Gamtoos River Crab 3 6 3 9 12
Rhabdomys pumilio Striped Fieldmouse 7 1 1 8
Acanthacris ruficornis Garden Locust 2 5 1 6 8
Pegylis sommeri Large Wattle Chafer 1 4 2 6 7
Lepidoptera Butterflies and Moths 2 2 2 1 5 7
Cyrtacanthacridinae Bird Grasshoppers 6 1 7 7
Afrogecko porphyreus Marbled Leaf-toed Gecko 1 3 3 4
Acrididae Short-horned Grasshoppers 1 2 1 3 4
Scorpiones Scorpions 3 0 3
Insecta Insects 2 1 1 3
Grylloidea True Crickets and Allies 1 2 2 3
Duberria lutrix lutrix Southern Slugeater 1 2 2 3
Coreidae Leaf-footed Bugs 3 0 3
Cicadidae Typical Cicadas 3 0 3
Sphaerotheriidae Southern African Pill Millipedes 1 1 1 2
Palystes Rain Spiders 2 0 2
Anax imperator Blue Emperor 2 2 2
Acherontia atropos Death's Head Hawkmoth 1 1 1 2
Trachylepis homalocephala Red-Sided Skink 1 1 1
Tettigoniinae Shieldback Katydids 1 1 1
Soricidae Shrews 1 0 1
Scarabaeidae Scarabs 1 0 1
Deropeltis erythrocephala Redhead Roach 1 0 1
Coleoptera Beetles 1 0 1
Cacosternum nanum Dwarf Dainty Frog 1 0 1
Araneae Spiders 1 0 1
Animalia Animals 1 1 1
Totals 146 99 155 156 410 556

Column A Total catches (M/F) 2020

Column B Male feeding female 2021

Column C Female feeding chicks 2021

Column D Male feeding chicks 2021

Column E Totals for 2021 (ex 2020)

Lähetetty 16. helmikuuta 2022 01:55 käyttäjältä colin25 colin25 | 5 kommenttia | Jätä kommentti

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