Invited speaker, Daniel Lees reported on his research topic. The following is an abstract of his report.
In the absence of data on sex ratios, conservation managers assume a 1:1 ratio which may not be the case, as males and females may exhibit differential dispersal, mortality, size, feeding behaviour and habitat use. With the appropriate data, management authorities could focus on threats to the limiting sex allowing the implementation of more successful management strategies (predator control, sign posting, exclusion zones and education)
In this study we examine whether sex-ratio variation is occurring in the Masked Lapwing Vanellus miles at the primary, secondary or tertiary level.
We radio-tracked 50 masked lapwing Vanellus miles chicks (50 broods) and compared body condition (growth rates; grams per day) and mortality (whether the male chicks were more or less likely to perish than female chicks) We also compared the body condition of all chicks within broods and to establish whether the time of the breeding season affects the brood sex ratio.
Chicks were no more or less likely to be male (or female) as the breeding season progressed. Male radio-tagged chicks (n = 27) were no more or less likely to perish when compared to female radio-tagged chicks (n = 21). At hatching, male chicks were no lighter or heavier nor had shorter or longer tarsi than female chicks Male chicks also grew no faster or slower when compared to female chicks.
This study detected no sex ratio variation or sex-biased survival among broods in the sexually monomorphic Masked Lapwing. This result was as expected and is in line with the Trivers and Willard (1973) hypothesis and the literature which details such variation exclusively among sexually dimorphic species.
Sex ratio variation among the Masked Lapwing
Monitoring survival of free-living precocial avian young is difficult. Perhaps the most promising methods available to determine survival are: (a) a combination of radio-tracking and frequent investigator brood visits or (b) targeted visits timed to mark young after hatching and then again to confirm fledging.
Our aim is to understand if the process of radio-tracking and the associated frequent visits negatively impact chicks when compared to infrequent targeted monitoring visits.
We radio-tracked 50 masked lapwing Vanellus miles chicks and compared body condition (scaled mass index) and within-brood mortality to examine whether attached radio transmitters influenced chick body condition or survival. We also compared the body condition of all chicks from radio-tracked broods to chicks subjected to targeted monitoring to examine whether investigator visits influenced body condition.
Within broods, there was no difference in body condition or mortality between chicks with and without radio-transmitters. Similarly, there was no difference in body condition between broods subject to radio tracking or targeted monitoring.
In agreement with the literature on the ‘glue on’ method of backpack radio-transmitter attachment, the body condition of lapwing chicks was not affected by radio-tracking compared with the targeted monitoring technique. Smaller, less robust and possibly less habituated species may still be negatively affected by radio-tracking. Radio-tracking seems an ethical and practical method for attaining an improved understanding of cryptic life history stages such as chick-rearing in shorebirds.
A Scaled Mass Index (SMI; a mass length relationship; Peig and Green 2009) was used to characterise body condition. All statistical tests were conducted in R (2015) with GLMMs of body condition conducted using the package ‘nlme’ (Pinheiro et al. 2014) and the Cox proportional hazard regression was conducted in the package ‘survival’ (Therneau 2015).
Peig, J. and Green, A. J. (2009). New perspectives for estimating body condition from mass/length data: the scaled mass index as an alternative method. Oikos118, 1883-1891. doi: 10.1111/j.1600-0706.2009.17643.x.
Pinheiro, J., Bates, D., DebRoy, S. S., Sarkar, D., and Team, R. D. C. (2014). Nlme: Linear and nonlinear mixed effects models. (R Foundation for Statistical Computing.)
Team, R. D. C. (2015). R: A language and environment for statistical computing. (R Foundation for Statistical Computing: Vienna, Austria.)
Therneau, T. M. (2015). A package for survival analysis in R.
Trivers, R. L. and Willard, D. E. (1973). Natural Selection of Parental Ability to Vary the Sex Ratio of Offspring. Science179, 90-92. doi: 10.1126/science.179.4068.90.
St Kilda is pretty close to the centre of Melbourne. Or is it? Well, it depends which one you are referring to. There is a very different St Kilda; an archipelago 100 miles off the north-west coast of Scotland, in the outer Hebrides. Katrina has spent time in both of them
St Kilda in Melbourne was named after the schooner, the Lady of St Kilda, which was moored on the front in Melbourne, in 1841. The woman called Lady St Kilda was in fact a Lady Grange, but was so named because her husband, a Jacobite, had her imprisoned on the islands for some years. The schooner was bought by Sir Thomas Dyke and named after a visit to the islands by his wife.
The island’s character is very difficult to describe, and the best account Katrina found was in a novel written by Hammond Innes called Atlantic Fury. It’s not an easy place to get to. It has less than 1500 people landing there a year, although many more people go there but the weather prevents them from landing. The main island is approximately two miles square, and it has the highest sea cliffs in Britain: over 1000 feet, and there are several stacks, two being over 600 feet tall. People have inhabited the island since the Bronze Age. The accommodation there reached 16 stone houses built in the late 1800s (which faced into the weather) and the common Scottish black houses (which did not), and there was a regular parliament meet by the men of the island.
The British Navy established a wireless tracking station, which operated during WWI and the island was shelled by a German submarine during that war, causing significant damage. However, the wireless tracking station was back in operation within two hours! Until then the island had no guns, but following the incident, a ship’s gun was installed and is still there. St Kilda was bequeathed to the National Trust of Scotland in 1957 then leased to the Ministry of Defence for a radar tracking station, and supplies and access to the island are largely dependant on that. The economy of the islanders was always based upon fulmar catches for oil and feathers for trade, and meat. There are over a thousand cleits on the island, which were used to store fulmar catches. Cleits and cottages interestingly contain stones with crosses from the four churches that were formerly on the island but subsequently demolished for building materials. Contact with the outside world put more pressure on the residents. There were major food shortages in 1876 and acute shortages in the early 1900s. Many islanders emigrated so that by 1930 there were only 36 islanders left and they also asked to be evacuated.
The St Kilda archipelago is one of the most important seabird breeding areas in north-western Europe. Today the island is dual listed by the UNESCO World Heritage, both land and marine. Katrina went there first with the National Trust of Scotland, sailing on a converted trawler that took 36 hours to get there from Oban. There is a sandy beach but it’s only accessible in summer. In winter one has to land by helicopter. Since then she has been back a number of times via transport laid on by the Army.
The Large Animal Research Group studies population dynamics of wild populations of the Soay sheep that have now been wild there since 1938. There is a roughly five-year population cycle, caused by weather and parasite loads and reasons for the crash are being sought. Sheep were fitted with recorders that fall off after 48 hours to measure sheltering and feeding. Snow is very rare on the archipelago because of the Gulf Stream which crosses the Atlantic Ocean from Central America.
There are half a million breeding seabirds on the archipelago and it has the largest population of the Northern Gannets in the world, with 60,000 pairs, mainly on the stacks. This is 19% of the world population. Only 1% of the world population is required to sustain a stable breeding population. There are 17 birds with high proportions of the world population, that nest regularly on St Kilda, including the puffin (2%; 230,000 occupied borrowers), Storm Petrel (89%), Common Guillemot (10,000 breeding pairs). There are Arctic Skua that attack from the ground and are very persistent. The Great Auk is extinct, but still three species of the family breed on St Kilda, of which the Razorbill is the closest living relative. Leech’s Petrel (89%) were only seen at night. They are attracted by light so everything has to be blacked out at night. Nevertheless, as many as 20 chicks a night could be easily caught and ringed. And the fulmars? It is interesting that, although 350 islanders caught 100 birds each per year, when the islanders left the fulmar population did not increase! There are also land and water birds there, including the St Kilda Wren, an endemic subspecies, much larger than the usual wren.
And Katrina’s greatest thrill? A quite unexpected white Peregrine Falcon – that was in fact a Gyr Falcon.
Thank you, Katrina, for showing us a St Kilda far more fascinating than our own.
So − you like to think you are adventurous. I know I did before I heard of Val and Peter Fowler’s adventures in Peru. I mean to say it’s one thing to go gadding around the world using real public transport, even going wild into Australia’s deserts for weeks on end, with all its risks. But that is nothing compared with travelling through a country like Peru, usually using local buses and taxis rather than simply going on an organised bus tour. It did have some advantages. They could stop whenever they wanted to get out of the taxi to watch or photograph some birds, much to the amusement or frustration of the driver. It had its disadvantages too, such as nearly being run down by a bus, almost falling into a raging torrent, and in some border towns, being under the very real threat of robbery. Furthermore, they had to carry their gear, with changes of clothing for the different climates they would experience.
But they did it ‘Their Way’, and they had a blitz of a time! And saw over 278 birds, far too many birds to mention here.
In 2013, Pete had three months long service leave, so they decided they would go to South America, spending two months in Peru. Val’s sister had been there and she gave them lots of tips and encouragement – not that they needed much, for they were experienced bush walkers and travellers. However, everyone they knew who had gone to Peru had either been robbed or knew someone who had been robbed, sometimes on three separate trips. It’s probably a vital National Industry. Because they were going to Peru for winter, and then to the Amazon they had to have several changes of clothing and had to carry everything. And everything stored had to be secured under netting.
They flew into Cusco, and travelled to Machu Picchu and Manu, then south towards Bolivia and Chile, then up the coast past Lima to the Ecuador border. They were a bit worried about the altitude of 3326 metres, but Pete had no trouble there. He had been much higher in the Himalayas, although Val was puffing a bit as they went uphill.
Even in Cusco there were plenty of birds in the main square, unconcerned with the people. They continued to Aguas Calientes, the starting point for Machu Picchu. They were close to the edge of a cliff, when a bus came down the hill fast and very nearly hit Val. As she stepped backwards Val slipped and nearly fell into the raging torrent below.
This was where they were looking for the White-capped Dipper and the Torrent Duck, that Val had only just avoided meeting underwater. However, they did see the birds above water, although they wondered how they avoided being swept away. They got to the terminus early, but there were already lots of people waiting for buses to Machu Picchu and they had to catch the seventh bus. Don’t be worried about the video cameras fitted in the buses. They are there just in case of accident; in case they can’t find you. Val and Peter had wanted to climb the mountain behind Machu Picchu, but only 400 people were allowed each day and it was fully booked. Instead they got permission to go to the top of Mount Machu Picchu. It took them three hours to get to the top (although they were continually being told it is only a half an hour to the top), and about an hour and a half to get down again. I suppose more birds got in the way going up! There was one guy who walked up the mountain every day, waited until the tourists had left, then came back down again collecting the rubbish the tourists had left behind.
Next day they visited an expensive hotel, the Inca Terra Hotel ($500 to 950 a night). Val’s sister had said that if they went in and said they were birdwatchers they would be allowed into the grounds. Although they were restricted to where they could go, they saw lots of birds in the beautiful gardens while the guests were out, sight-seeing.
They had booked (in Australia) a tour with Manu Wildlife Tours, owned by Barry Walker (British Consul General) and his wife, and had to make a final payment, but it was hard to find the place. It was finally found, looking like the back of someone’s house with lots of warnings about robberies. It must officially be a National Industry.
The tour took them first to see pre-Inca ruins near Lake Huacarpay but there were unexpectedly few birds on the lake; probably just the wrong season. In a market place there were piles of coca leaves that the locals chew to help with the high altitude; perhaps as well as everyday worries, for the leaves contain low levels of cocaine. The next stop was the southern most tip of Manu Forest National Park, a cloud forest only accessible to researchers. But there was good birding along the edge of the forest. From there they travelled past more land-slips and road-works to the Cock of the Rock Lodge, a site for one of Val’s important must-see birds. Val only got the briefest glimpse of the Cock of the Rock, until much later. However, at the Lodge Val and Peter were told of a humming bird that could not be identified. It was not until Val managed to get a photograph that they found it to be a humming bird hawk moth, behaving and sounding very much like a small hummingbird. It was a good spot for birding.
On the way to their next stop they were happily held up for two hours by road works – a good opportunity for birding. Surprisingly, there was a party of American birdwatchers also trapped in the jam − who never got out of their car. Two hours later the tour arrived at at the Rio Madre de Dios, a fast flowing river that was quite choppy, with rocky banks. They were too late to stop, but saw lots of birds and a family of capybara churning up the bank like 4WD hoons. There were precariously placed houses on the riverbank that could have easily been swept away, and dangerous trees and logs in the water. They arrived after dark at the Romano lodge on the Manu River, which turned out to be much sandier and many birds were seen there.
Here it was obvious that some spots were more popular for birds and butterflies. It turned out that these was where the boatmen urinated while waiting for their passengers; you know − increased nitrogen, increased algae, increased water insects, increased vegetation, more birds. Just like the WTP. The Manu Wildlife Centre was very disappointing. Val reckoned that whoever produced the list of 600 birds there was flying on coca leaves, although there were numerous tiny black dots on faraway trees. There were, however, good paths and hummingbird feeders. Here they met the tapir that drooled as Pete scratched it behind the ear and under its chin. There was a clay, salt-lick that was very disappointing, with only a solitary common parrot visiting.
From there they flew back to Cusco and started towards the coast, past Lake Titicaca with its floating islands of reeds. There was a walkway, and paddle boats for kids and although there was a lot of rubbish there were still plenty of birds. But it was so cold at night they had five blankets and it was difficult to turn over at night. At one place, Val and Pete hired a taxi for a half-day trip to ruins with a nearby lake. The driver was amused that they were more interested in the birds on the lake, looking at his watch and anxious to get on. They visited the Colca Canyon, which is twice as deep as the Grand Canyon, and saw the Andean Condors soaring on thermals. When they stopped for lunch, Peter got blue lips and serious symptoms of altitude sickness and there was concern he could go no further, but given a cup of coca tea, Pete started to feel better. However, going over a high pass later, Pete still wanted to stop the bus to get a photo. He had no more trouble with altitude sickness. Instead, three days later in a plane over the Nazca lines, Pete was green through motion sickness!
While walking up the coast towards Lima, they met a guy staying at a hotel nearby. It was lunchtime so they decided to stop there for a sandwich lunch. They were startled at the price – til they realised the hotel was sister to The Hilton. Eventually they reached Lima on the sand dunes. There had been no rain for 10 years and all the water had to come down from the mountains. Here they saw a local girl being robbed – the local National Industry in action again. Val and Pete visited Kennedy Park, home to numerous wild cats fed by locals who showed clear favouritism for the prettiest ones. From there they travelled north to Chaparri Lodge. The Reserve (in photo below) was owned by the local community and employs only local guides. It was the first reserve sponsored by the 2004 British Bird Fair and was established in 2000, comprising 34,000 hectares. This was Val’s favourite spot on the entire adventure.
Then, surprise, surprise, at Chiclayo, Val and Pete were invited to a meeting of the 2nd bird challenge rally. This event was much more serious than any challenge count that they had been on. There were six teams: two from the USA, and one from each of Spain, Brazil, the UK and South Africa. There were six members per team and the leader had to have proven conservation experience. In addition, they had to give conservation plan advice to each local community visited. The winning team counted 636 birds in eight days and overall, 864 birds were spotted − 10% of the world population. While there, Val was given a bird book by an artist on a park they had not intended to visit. So they had to go there! Bosque de Pomac had pre Inca ruins and good birding with Blue-white Swallows covering the walls of the Sipan pyramids, that Pete simply had to get permission to photograph. In the ruins, Burrowing Owls took no notice of people – who incidentally took no notice of them.
From there Val and Pete travelled inland to Chachapoya where they hired a taxi (complete with a mad taxi driver) to go to Huembo, which was also sponsored by the British Bird Fair, but near where two British birders were murdered while looking for the Magnificent Spatulatail Hummingbird. This bird was on Val’s most-wanted-bird list and they safely found it.
From there they visited the Cerros De Amontape National Park, the largest dry tropical forest in the world. Val and Pete were aghast at the ruthless slashing of riverside vegetation for access by stock. What was worse, even their guide was slashing vegetation in the park, perhaps in the manner of an explorer in jungle that we so often see on TV movies. They were now very close to the end of their Peruvian holiday as they entered Tumbes, a border town between Peru and Ecuador, where they nearly fell foul to the National Industry. All they wanted to do was walk down the road to the nearby supermarket. However, as soon as their intention became clear they were stopped. ‘Don’t go!’ they were told. ‘You’ll be robbed before you get halfway!’
So ended what must have been one of the most interesting and exciting holidays Val and Peter had ever taken. Peter told us that he had spent a couple of months planning the trip using the Lonely Planet Guides, whereas Val looked at trip reports first. If you have plans to travel overseas, to even less difficult places, you would do no harm chatting to these intrepid wanderers. Even to Europe; I have been robbed twice in two separate journeys to Italy. It’s actually part of the International Tourist Industry!
Thank you, Val and Peter. I haven’t enjoyed myself so much for seventy years, since I read of intrepid explorers in ‘Boys Own Magazine’.
Illustration and photographs by Val and Peter Fowler
Our Birdlife Melbourne BBQ was a great success, as you have probably already heard. Committe member, Millie Scicluna organised the event (with her parents doing the cooking), and salads provided by various other members. But the surprise you may not have seen was the Striated Pardalote at nest which Millie found in the carpark.
On the following Monday I visited the bird again and made this HD video of the bird singing away on his doorstep. That seemed to be a hazardous occupation, but he was obviously pleased with himself.
Adriana can now show us videos on our blog – so here is the Striated Pardalote:
Last July, Bill and Shirley spent eight nights in Iceland and visited Lake Mývatn, and Bill talked about some of the birds they saw less than 100km from the Arctic Circle. They found the scenery spectacular, with lots of geothermal activity and a couple of geothermal power stations. There were lava flows, volcanos and many trapped steam vents and thermal springs. Two thousand three hundred years ago a fissure eruption over a lake caused evaporation of the water beneath the lava and the formation of pseudo craters.
The lake is shallow and 37 square kilometres in size with an average depth of 2.5m and maximum depth of 4.5m. Black sand and rocky beaches border the lake, with plenty of vegetation for good nesting sites. And good food too. There were innumerable midges which, thankfully for Shirley, did not bite. The birds there were a mix of Northern Eurasian and American migrant species including the Great Northern Diver and Horned Grebe. The lake is the source of a fast river and they watched a Harlequin Duck chick surfing on fast water, apparently quite unperturbed by the adventure.
There is plenty of accommodation nearby but the lake and rivers are preserved, although there is a camping ground on the shore. Volcanos erupt about once in every five years. So the vulcanologists are continually having to come up with new names. Some of the names are so strange it seems they have simply placed a cat on a keyboard to come up with the next one.
Food for thought at the end of Bill’s talk: ‘Why do birds always stand on white rocks?’
Balwyn meeting report, 23 June 2015 Guest speaker: Sonja Ross
In October 2014, Sonja lived a dream of her lifetime. At last she got to see Africa. Sonja and Geoff flew into Nairobi and were immediately rewarded with their first view of Superb Starlings in the airport car park.
Preston, their guide for the trip, was a specialist birder who had contributed to finding birds for the field guide. In the off-season he taught local students, free of charge at his home, about African wildlife. While on safari, they could only walk around the vehicles on a main meal break but even then only after the guide had checked for predators from a high hill. Being restricted to the cars reduced Sonja’s ability to photograph birds, especially the smaller and faster ones. Nevertheless, in just 16 days Sonja managed to add over 265 birds to her life-list and to photograph many of them. Quite enough to keep her audience enthralled.
Because of the heat at midday, they met their guide at 6.30am and stopped for lunch at about 11am. From then to about 3pm they rested or spent time with chores and managing photographs. But they were ever made aware of danger and were required to be back at the accommodation by 6pm. When the sun goes down, danger outside increases.
Sonja presented her photos in taxonomic order rather than temporal. This probably suited most long-time birders by helping them relate to the birds they had already seen in other environments. My personal perspective is closer to the ecology of the birds and other creatures so I would have been more comfortable in a traditional approach. But then my bird list is very small, although I have travelled widely in several countries. Whatever one’s personal preference, Sonja’s presentation was a very professional one, with interesting and quality photos and videos expertly presented and enjoyed by all.
There were so many photos that I can hardly begin to do justice to them. It will have to suffice for me to recall some that stuck in my mind. For example, there were the Sand Grouse that nest far from water, causing problems when raising chicks that need water daily. The males have special feathers they can soak with water and carry it back to their young. They might have to fly 50 km several times a day when rearing young.
The Crowned Lapwing was nicknamed by Geoff as the one with the Collingwood beanie, which then gave Sonja the difficult task of explaining to Preston what a Collingwood beanie was.
The Secretarybird is a raptor with long legs that it uses to flush from tussocks the snakes it preys upon, requiring very fast reflexes.
Vultures are fascinatingly ugly birds that have few feathers on their necks. Well, wouldn’t you prefer that if you spent so much time with your head inside a carcass?
And there was a Yellow-billed Oxpecker that enjoyed the task of relieving a giraffe and other animals of its pest insects, which they eat.
We will all have to await with anticipation the story of her next adventure, now that Sonja and Geoff are both retired – if they really have; after all, photographers never do.
Balwyn meeting April 2015 report. Guest speaker: Oliver Hornung
I have worked in agricultural research or over 40 years, in the United Kingdom and in Australia, but found Oliver’s talk both interesting and informative, but also rather disturbing. My work had always been in a rather specialised topic of plant pathology, and I was quite unaware, not so much of the impact of agriculture as of the impact of animal agriculture. In those early days one of the major research projects in the UK was the direct production of protein from crop plants. It was well recognised even then that the production of protein through livestock was an inefficient process. Oliver’s well researched and referenced talk showed me, just how inefficient that process was.
Although he first showed that world agriculture used 37% of our land area, equivalent to that of Asia – that did not surprise me. Oliver then showed that 22% of the land was forest, 9% was grassland, 22% was barren and two or three% was urban. But he also showed that the large majority (70%) of agricultural land use was for animal agriculture, and that did surprise me. When the land used for the production of stockfeed (about 10%) was also taken into account, the land left for other crop plants was surprisingly much less than I had expected.
Most animal production relies heavily upon grain, fed in some kind of feedlot, but in addition, over 25% of fish production is actually used in animal production. Ninety percent of cattle, 98 % of poultry and 70% of sheep are grain fed. Oliver went on to show how much grain was used to produce one kg of the meat of different kinds of animals. For example, he showed that two kg of grain was required to produce one kg of chicken meat, four kg of grain to produce one kg of pork and 7-14 kg grain to produce one kg of beef.
Water is, of course, widely used in agriculture. Of the world’s water production, 70% is used in agriculture, 10% is used by households and the remaining 20% is used by industry. In his succeeding graphics, Oliver used a bath tub to symbolise 140 litres of water. To produce one kg of grain, approximately 3,221 litres of water is required. However, 4,300 litres was required to produce one kg of chicken, more than 10 times that is required to produce a kilogram of pork and the production of 1kg beef required 110 bath tubs or 15,000 litres of water. The production of a single Burger requires 2500 litres of water.
Waste production in animal agriculture is a major problem, especially in relation to water quality because it enters the environment in an untreated form. For example, 5,000 pigs produced the waste equivalent of 20,000 people and 5,000 steers produced nearly the waste equivalent of a million people. In the United States alone, 40% of the land area, and 56% of the water is used for animal agriculture. Animal agriculture produces 130 times the waste of the entire population.
Land is also a major resource in agriculture. A meal based upon pork requires the use of 3.12m square of land, a single hamburger requires 3.61m square and a chicken curry requires 1.36m square. In contrast, only 0.19m square is required to produce a plant-based diet. Overall, a vegetarian diet results in 50% less carbon dioxide than a diet based on meat, produces one third the waste, uses less than 10% the water and 1/18th the land.
People in developed countries consume 20 times the meat and dairy products above the world average, and that proportion is expected to increase. Although population growth has been steadily decreasing over recent years, the human population is still increasing, and there is no sign of that changing. Agricultural industry ranks second in its contribution to climate change. A major factor is that the production of methane is more serious than the production of carbon dioxide. Although it has been estimated that by improving agricultural techniques it would be possible to obtain net zero emissions of glasshouse gases by the industry. However, inevitable population growth will continue to make more demands on land and other resources used in agriculture.
Habitat loss is the most important single factor reducing biodiversity. It is responsible for 85% of threatened species, both plant and animal, and although attempts are made to mitigate the problem by replanting forest and bushland this only results in one tree planted for every 100 cleared. Queensland has the largest amount of forest remaining in Australia, but it also has the highest current rate of forest removable, and 92% of the cleared land is for animal agriculture. Nearly 80% of that land clearing on the east coast of Queensland results in increased run-off to the Great Barrier Reef and consequential loss of coral.
With regard to loss of biodiversity, high grazing regimes result in low diversity although numbers of some common species increase. These include Noisy Miner, Masked Lapwing, Crested Pigeon and Australian Wood Duck. On the other hand, light grazing retains more habitat diversity and so retains more bird and animal diversity. Under such regimes birds such as Brown Thornbill, various fairy wrens, White-browed Scrubwren and honeyeaters can survive. However, with the loss of any particular habitat, particular species must necessarily also be lost. It was suggested that most birds susceptible to habitat loss through grazing have already been lost. Personally I doubt that. Although habitat loss has been occurring for over 300 years, the majority of that would have been in the last 150 years or so, and it does seem to be a never-ending process. So many species seem to have small, localised habitats and have nowhere to go if those habitats are lost. That seems a bleak future for biodiversity.
But Oliver did not talk about human population growth. Man’s future on earth may be even more bleak. I personally suspect that, if we double our population over the next 60 to 100 years, as seems likely, we would need to double our agricultural production. Unless we greatly improve our agricultural practices, or reduce our demands on land, we will have no more new land to use thereafter. With our current population at about s billion, our maximum sustainable population could perhaps be as little as 50 billion. And we could be in sight of that figure within 100 to 200 years.
We must surely start to do something about that now.
Invited speaker: Alisa Bunbury, Curator of Prints & Drawings, The National Gallery of Victoria
At our Balwyn meeting in March, Alisa Bunbury presented a talk on John Lewin’s art in the context of the early colonial natural history artists, with illustrations of paintings of the day. These were in part drawn from the Prints and Drawings Collection of the National Gallery of Victoria, which make up about one third of the Gallery’s collection. In that collection there are 16 plates from John Lewin’s Natural History of the birds of New South Wales, purchased with the help of the Stuart Leslie Foundation.
It was interesting to note that, by the time of the arrival of the First Fleet in 1798, Citizen Science had already been invented. People of private means, or sponsored by wealthy collectors, had become amateur naturalists, sending all kinds of Australian plant and animal specimens home to numerous collections in institutions and private homes throughout Europe. With this explosion of knowledge, there was also a need to disseminate the information and that required drawings, paintings and etchings.
In early Australia the artists were either ship’s crew or convicts who made the original illustrations, as well as copies; even re-copying those done by others. The early convict artists are grouped under two names: the Port Jackson Painter and the Sydney Bird Painter. However, styles show there were many painters, with much copying being necessary within and outside Australia in order to satisfy the very wide demand for information. Thus, errors were often perpetrated or introduced, and there is much uncertainty concerning the artist responsible for particular paintings.
The first illustrations of Australian natural history were made by amateur artists during Dampier’s first voyage, although on his second voyage in 1699, he had a skilled artist on board.
Having circumnavigated New Zealand, James Cook sailed to the east coast of Australia in 1770, with Joseph Banks and his entourage of eight, including the artist, Sydney Parkinson, who made 130 sketches, but only one of a bird – the Red-tailed Black Cockatoo.
Professional artists working with bird skins included Thomas Watling and the London-based Sarah Stone, who was very talented, but the birds do not look natural, and the appearance was much determined by the way the skin was prepared.
John Lewin was born in 1770 and grew up mostly with the natural history of his time. His father William Lewin was a leading ornithological artist, although he had started a fabric industry in the East End of London. He produced a handbook of the birds of Great Britain, between 1789 and 1794 and painted all of the 323 illustrations of the 60 copies, nearly 20,000 watercolours. William was elected to the Linnaean society in 1791. A second edition, using etchings in place of drawings, was started by William and completed by his sons John and Thomas after his death in 1795.
Thus, John was an experience collector and illustrator, was skilled at etching, and had good connections with his father’s natural history friends and publishing contacts. Furthermore, John had already illustrated Australian birds as early as 1798, before he emigrated to Australia. For these reasons, the Colonial Secretary, the Duke of Portland, suggested to Governor Hunter that Lewin’s skills would be useful in the colony and recommended that he receive the usual government rations while in Australia. John was also sponsored by Drew Drury, who had an extensive collection of insects that already included specimens supplied by William Lewin in 1759, in exchange for additions to his collection. Drury supplied the equipment of collecting and storing insects and plates for etching, and 61 pounds ten shillings and sixpence. John also took with him printing inks and a small printing press, the first in the Colony. Alisa told us, however, that he actually missed the ship, and his wife sailed without him and had to cope for herself for 10 months until he arrived on the next ship in 1800. By the time of Lewin’s arrival, Sydney was 12 years old and comprised about 5000 residents of which 4000 were convicts.
Alisa’s slides clearly showed that Lewin brought a new level of sophistication to the art, for he was the only professional artist employed in the Colony. Initially, his paintings were classically of birds on a branch against a blank background, but with a fresh realism some 30 years before Audubon. This was because he was now making illustrations by direct observation of living birds (below right), instead of the skins he saw in England (below left).
He specialised in the smaller birds, rather than the spectacular parrots and cockatoos and was elected an associate member of the Linnean Society. Thereafter he always appended the initials ALS to his name. His skill at painting birds was only matched by Bower but John’s prints were the first to be produced in the Colony.
John planned to produce all the prints of his first book on insects himself but ended up sending the plates to London to be printed there and combined with text written by Thomas and entomologists. Unfortunately, Drury died in 1805 and did not see the book. By that time, Lewin was receiving private and government commissions. In 1806, Lewin set out to publish a set of 18 bird prints by subscription. Once again he sent his plates to London for printing in 1808, rather than print them in Australia. However, the shipment of copies for Australian subscribers never arrived, presumably through some disaster. Some copies have survived from the English subscribers and four of these are held in Australia and two in London.
In 1813, Lewin made 13 copies of the 1808 book using a mix of trial prints and reworked plates. If he did not have enough copies of a particular bird, he replicated it in watercolour. Those prints, coloured by John and his wife Maria, show a freshness not seen in the commercial copy. Four copies exist in the New South Wales Library, one is in the National Library of Australia and one in the Natural History Museum in London. The one in the Latrobe Library in Victoria was purchased for five pounds compared with the last sale price of some $500,000.
John Lewin died in 1819, aged 49.
Alisa gave us a fascinating tale of the problems surrounding early colonial art, well illustrated with artworks in Australian and overseas collections. If we wish to see some of the original illustrations, we will have to be vigilant or lucky, for prints and drawings have to be rotated in order to protect them from light and there are many of them. She obviously enjoyed researching the early illustrations of birds, perhaps because she has a few relevant genes. After all, her parents were instrumental in having Yarra Flats declared a park. And she has recently purchased some binoculars!
Caroline Wilson trained as an urban ecologist and has extensively studied bats, although she has previously studied Whiskered Terns on Mud Island and Grey-crowned Babbler habitat in north east Victoria. She is now a Project Officer studying woodland bird environments for BirdLife Victoria.
Bats fly more efficiently than birds; they fly faster and use less energy. This is because they have a wing membrane, less air resistance and joints in their wing bones. In fact, bats can out-manoeuvre owls. They prefer to nest in hollows in trees and, like birds, they feed on nectar and insects. There are over 1000 species in the world, from micro-bats to the large fruit bats. Their economic value in the agricultural industry is about $3 billion annually in the US, where farmers even put out nest boxes for the bats. Bats are important for long distance dispersal of seed and pollen, especially fruit bats along the east coast of Australia.
Microbats are the most common kind of bat in Melbourne, in particular Gould’s wattled bat and the Lesser long-eared bat. Although the sounds of most bats are beyond the frequency of our hearing, and can only be heard using bat detectors which lower the frequency of the echo-location calls, we can actually hear the call of the white striped freetailed bat. There are 16 species of micro-bats in Melbourne, and are found throughout the suburbs. However, as you get closer to the city, urbanisation reduces the number and species present. In general, the narrowing bats can fly better over urbanised spaces, can use artificial nesting places, and so survive better in built up areas. This is important in urbanised areas, where the numbers of trees with hollows have declined from about 22 per hectare to six per hectare.
Because Caroline needed a large sample size for her studies, she chose the Gould’s wattled bat, for it is the species most common and widespread. She chose three sites; the Royal botanic Gardens, a typical ornamental city park, with many exotic trees; and Valley Reserve and Blackburn Lake as examples of bush parks, with many 40-year-old native trees. Small radios, weighing less than 0.5 g, were fitted to the bats, using silicon glue, in order to to track the bats. The radios were slowly lost through grooming.
Because bats change roosts regularly, in order to reduce parasites and predation, the bats had to be tracked daily. A total of 135 roost trees were found, mostly within the parks and reserves, although at Blackburn Lake many were also found in nearby gardens, which often contained mature native trees. When a roost tree was found, characteristics (state of decay, diameter, height, species) of the tree were measured, together with those of sample trees within a 50 m radius. This was to see what was available for roosts, and what was chosen.
In parks, bats tended to choose cavities in decayed trees, especially beside walking tracks, which gave the bats more open space to escape into or hunt. Unfortunately, these trees are often removed during park maintenance. In the Royal Botanic Gardens there are not many decayed trees. Instead the bats use the eight cypress pines there, with deep crevices in the bark, and the dead fronds of palms. Such roosts are less insulated than tree hollows. In these trees, the most common roosting site was unusually low and much wider than the bat, making it more susceptible to predators and weather than usual. In the Botanic Gardens and in urban areas, where there are fewer preferred roosting sites, bats were re-using roosts more often than in the bush parks.
In order to discover what habitat features they are using, 21 bats were tracked over night, recording their positions ((GPS position, direction and signal strength) at 15 minute intervals. Bats foraged up to 1500 m from the roost site, preferring sites with a high density of trees and proximity to water. Thus they spent most of their time within the reserves, especially within the Botanic Gardens, where there is little green space and water within the nearby urban area.
How does urbanisation affect bats?
Six study sites of different degrees of urbanisation, were defined in terms of numbers of tree and amount of closed space (roads, buildings), with 10 observations within each. A light trap and bat detector was set up at each site.
Some 70,000 insects were caught in the light traps and identified down to order. In terms of biomass, there was a negative correlation with the roads (urbanisation), distance to water and urban light and a positive correlation with temperature and numbers of trees. The bat detector results showed that bat numbers increased linearly with insect biomass over the 60 observatins.
Caroline left me with many issues in my mind of these cute (I think of them as gothically beautiful) animals.
Dead trees are important for urban bats: Councils could help to conserve bats by trimming only those dead branches by walking tracks, leaving a safe part attached to the tree. The same could apply to our gardens with benefit for bats and birds.
Palm trees can be used as alternative roosting sites, as well as trees with suitable (rough or stringy) bark.
More trees mean more prey for bats (and birds).
Although nest boxes are used by bats, only six of the 16 species in Melbourne use them. There needs to be studies on designs suitable for other bat species.
Since preferred foraging locations have lots of trees near water, perhaps we need more ponds or fountains in parks, to provide more food for bats and birds.
Rodger Scott told us that the sanctuary is located to the south of the city of Vancouver, just north of the US border. In the 1960s, George H. Reifel, the son of George C. Reifel, granted the first lease to the British Columbia Waterfowl Society for a bird sanctuary to be named after his late father. Ducks Unlimited Canada, an amateur hunting group, was brought in to assist with water management of the many wetland habitats on the site, and has continued to be an active partner in the management of the area. The provincial government supplemented this effort by establishing a game reserve on the adjacent intertidal foreshore. It is not uncommon to hear gunshots from the game reserve as you walk around the sanctuary, which caused Rodger some discomfort.
It was Rodger’s second visit to the Reifel Sanctuary, in which over 250 bird species have been recorded. Although it was cold it was sunny, making the weather good for photography. There were large numbers of waterbirds and plenty of bush birds, and he saw many new species.
The visitors to the sanctuary feed the birds. In fact, on entry one can buy feeds for the different kinds of birds. For this reason it was almost impossible not to step on them, and many are so tame they would eat out your hand. That made it excellent for photography.
Rodger showed us some of the birds that he had encountered, including Black-capped Chickadee, Chestnut-backed Chickadee, Red-winged Blackbird, House Finch, Cedar Waxwing, Song Sparrow, Golden Eagle and others, including his favourite Canadian bird, the Red-breasted Nuthatch.
Rodger missed a Great-horned Owl that had been unexpectedly seen in the open, looking down on people in a photogenic manner, but managed to see photos taken by others.
Each year, Snow Geese leave Wango Island north of Siberia and some 20,000 of them arrive at Vancouver in October, where observers with telescopes record their tags and numbers. These birds must like the cold, for they spend the winter in Vancouver then fly back to the Arctic for the summer.
Other birds Rodger talked about included the Black-crowned Night-heron, as well as the Blue Heron, a big bird, and quite a formidable predator. Apparently Blue Herons even eat prairie dogs. They split them with their bill, toss them into the air and eat them. The Sandhill Cranes also have a long sharp bill, so Rodger wisely kept well clear of them!
We all enjoyed Rodger’s talk but it does raise a question: Is it the traveller that makes the birder, or the birder the traveller? A good bet is both!