Archive for October, 2006
October 25, 2006 Edition 1
The Mercury (subscription), South AfricaÂ
At last people are talking sense about the plight of the barn swallows at the Mount Moreland roosts (The Mercury October 19).
In the past even some ornithologists have been heard to say that the swallows don’t matter, but put in the context that the roost accommodates at least 13% of the known population makes the threat to the roost, if Dube Tradeport goes ahead, an international crisis.
I have been monitoring the swallows since 1992. There are two roost sites at Mount Moreland, one on each side of the village. The mitigation for phase one of the tradeport was that the majority of any storm water run-off would go through the smaller wetland, but nobody from the Institute of Natural Resources, who are meant to be doing the EIA, had checked whether any swallows roost there. They do.
I think the estimate of three million birds could be very low. We know that between 700 000 and two million birds come in to roost on any one night (and that does not include the birds on the other side of the village). What we don’t know is how many of these are resident or just passing through.
My hypothesis is that the roost is more a “motel” than a residential hotel. If my thoughts are correct, and I base them on the fact that the numbers each night vary greatly, then the actual number passing through the roosts each year could be 10 times higher than the three million suggested.
With regard to air strikes, I don’t think that 18gm of barn swallow, even if consumed in large numbers, is going to have much effect on a modern jet engine which is designed to withstand much larger birds.
October 31st, 2006
The Tree Swallow, Tachycineta bicolor, is a migratory passerine bird that breeds in North America and winters in Mexico, Central America and the Caribbean. It is a very rare vagrant to western Europe.
This swallow averages 13.5 cm (5 inches) long and weighs about 20g. The bill is tiny. The adult Tree Swallow has iridescent blue-green upperparts, white underparts, and a very slightly forked tail. The female usually has duller colours than the male, often more greenish than the more bluish male. The juvenile plumage is dull grey-brown above and may have hint of a gray breast band.
Breeding
Tree Swallows nest in natural or artificial cavities near water and are often found in large flocks. They also readily nest in nest boxes maintained by people, often for Eastern Bluebirds. Habitat loss is a concern for Tree Swallows.
The Tree Swallow nest consists of multiple layers of small twigs and grasses and is lined with large feathers. (As such, it is easy to differentiate from that of an Eastern Bluebird.) The female lays 4 to 6 white eggs and incubates them by herself. The eggs hatch in about 14 days and the hatchlings are not precocious and need to be fed by both parents. The hatchlings typically fledge in 16-24 days. Tree Swallows sometimes cover their eggs with feathers when leaving the nest unattended.
Tree swallows typically have only one brood in a year, although there are records of a second successful brood.
They subsist primarily on a diet of insects, sometimes supplemented with small quantities of fruit. Tree Swallows are excellent fliers and take off from their perch and acrobatically catch insects in their bills in mid-air.
References
BirdLife International (2004). Tachycineta bicolor. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006. Database entry includes justification for why this species is of least concern
[edit]External links
October 30th, 2006
ehow.com
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Difficulty: Moderate
When swallows migrate in spring, they immediately begin looking for textured surfaces to attach mud nests to. Keeping nests from being built on the eaves of your house involves dealing with each nest as it’s constructed, or denying the birds access before they begin building. The latter is called the “exclusion” method.
Instructions
STEP 1: Purchase enough netting - with a 1/4- to 1/2-inch mesh - to stretch from the outer edge of the roof to the side of the house.
STEP 2: Gather tape, staple-gun or hooks to mount the netting.
STEP 3: Mount the netting so it extends from roof edge to wall, thereby making eaves inaccessible.
STEP 4: Try hanging a curtain of aluminum foil, plastic sheeting or sheet metal from a wire strung just above where roof overhang meets wall as another option.
STEP 5: Use a hose with long, reaching adaptors to wash nests out, or knock them down with a long-handled pole or broom. Make sure nests are just being built and don’t contain eggs or young.
Tips & Warnings
The time to begin swallow control measures is January, before birds migrate north in the United States and begin to breed.
Once swallows have laid eggs or have young in a nest, it is against federal law to destroy or disturb the nest in any way.
Shooting or otherwise harming swallows is against federal law.
October 20th, 2006
.findarticles.com
Auk, The, Â Jul 2002 Â by Chaplin, Susan B, Â Cervenka, Mora L, Â Mickelson, Alison C
ABSTRACT.-We continuously recorded temperatures of the nest cup (T^sub n^) and air (T^sub a^) just outside the nest box throughout development of Tree Swallow (Tachycineta bicolor) chicks in east-central Minnesota. Brood size was manipulated (three or six chicks per nest) to study the effect of number of chicks in the nest on its thermal environment. From day 0 to day 4, T^sub n^ paralleled T^sub a^, approximately 2-7 deg C higher, with nocturnal T^sub n^ maintained at 24 deg C and daytime T^sub n^ maintained at 26 deg C. From day 6 to day 12, T^sub n^ was relatively constant throughout the day, maintained at 32 deg C (day) and 29 deg C (night). The T^sub n^ became increasingly independent of T^sub a^, as determined by regression analysis of T^sub n^ versus T^sub a^ with age. Nocturnal T^sub n^ of larger clutches (six chicks) was -2 deg C warmer than smaller clutches (three chicks), and T^sub n^ of larger clutches exhibited greater independence from T^sub a^ at day 10 than in smaller clutches. The occurrence of nest homeothermy at day 10 in six-chick nests correlates with near-maximal body mass of chicks and completion of feather insulation. Small (three-chick) clutches showed greater dependence of T^sub n^ on T^sub a^ at 10-12 days of age than large (six-chick) clutches; we propose that development of thermoregulatory capacity may have proceeded more slowly in chicks from those nests.
RESUMEN.-Registramos continuamente la temperatura de la copa del nido (T^sub n^) y del aire (T^sub a^) inmediatamente exterior a la caja de nidificaci6n durante el periodo de desarrollo de polluelos de Tachycineta bicolor en el centro-este de Minnesota. Manipulamos el tamaho de la nidada (tres o seis poIluelos por nido) para estudiar el efecto del ndmero de polluelos en el nido sobre el ambiente termico de este. Desde el dia 1 al dia 4, T^sub n^ fluctuo en forma paralela con T^sub a^, pero fue aproximadamente 2-7 deg C mayor; la T^sub n^ nocturna se mantuvo a 24 deg C mientras que la diaria a 26 deg C. Desde el dfa 6 hasta el dfa 12, T^sub n^ fue relativamente constante a traves del dia, manteni6ndose a 32 deg C durante el dfa y a 29 deg C durante la noche.
Mediante un analisis de regresion de T^sub n^ versus T^sub a^ determinamos que la independencia entre T^sub n^ y T^sub a^ fue incrementando con el tiempo. La T^sub n^ nocturna de las nidadas grandes (seis polluelos) fue -2 deg C mas alta que la de las nidadas pequenas (tres polluelos), y al decimo dia la T^sub n^ de las nidadas grandes presento una mayor independencia de la T^sub a^ que la de las nidadas pequenas. La presencia de homeotermia en el decimo dia de los nidos con seis polluelos se correlacion6 con la masa corporal maxima de los polluelos y con la finalizaci6n del aislamiento por plumas. Con 1012 dias de edad, T^sub n^ mostro una mayor dependencia de la T^sub a^ en las nidadas pequenas (tres polluelos) que en las nidadas grandes (seis polluelos). Proponemos que el desarrollo de la capacidad termoregulatoria podria haber procedido mas lentamente en polluelos de nidadas mas pequenas.
Tree Swallows (Tachycineta bicolor) begin breeding in April in Minnesota and the first young hatch approximately 1 June, when air temperatures at night may range from 5-15 deg C. On cool days and during inclement weather, average daytime air temperatures at that latitude may only be 15-20 deg C, posing significant risk of cooling to newly hatched chicks without an attendant brooding parent. Perhaps because of the risk of hypothermia associated with early breeding at northern latitudes, Tree Swallows line their cavity nests of dry grass with feathers (Robertson et al. 1992). The importance of that feather insulation was documented by Lombardo et al. (1995), who found that Tree Swallow chicks from nests with artificially reduced feather insulation had lower growth rates and were smaller and less mature at day 12 (approximately two-thirds of the nestling period).
Few measurements of nest thermal environment during posthatch chick development have been reported. Calder (1971) recorded temperatures of artificial eggs inserted into two Calliope Hummingbird (Stellula calliope) nests by continuous recording during incubation, brooding of young chicks, and late postnatal development. However, most studies have focused on nest or egg temperatures during laying and incubation periods (Haftorn 1978, Cooper and Afton 1981, Zann and Rossetto 1991, Smith and Montgomerie 1992, Flint and Maccluskie 1995, Wilson and Verbeek 1995). This study reports results of continuous recording of nest cup and air temperature (at the surface of the nest box) throughout Tree Swallow nestling development and as a function of clutch size. On the basis of the premise that nest temperature is critical to nestling development, several questions have been investigated with these data. (1) How is nest temperature influenced by the ambient environment (air temperature, variation in air temperature, or time of day)? (2) Does the number of chicks in the nest affect the thermal environment of the nest during development? (3) How is nest temperature influenced by growth and maturation of chicks-that is, does the pattern of nest temperature change daily during the nestling period, specifically with changes in nestling biomass and development of endothermy?
Methods.-Tree Swallows were studied at the Twin Cities Army Ammunition Plant, New Brighton, Minnesota, from 1995 through 1997. Over 400 bluebird (Sialia sialis) nest boxes had been installed on the 2,400 acre site during the previous six years. Pairs of nests in close proximity and with similar hatch dates were selected for continuous temperature monitoring. Clutch size was reduced to three young in one nest, and was held at six in the other. Data loggers (Model ML-1, Mini-Mitter Co., Bend, Oregon) were installed in six pairs of nests to record air and nest temperatures throughout chick development.
Prior to their installation in nest boxes, probes for the data loggers were calibrated in a water bath against a reference thermometer over a temperature range of 20-40 deg C, were programmed to log temperatures 10 times an hour throughout the day, and synchronized with real time. Response time of the external nest probe was
To evaluate the effect of air temperatures on nest temperature throughout development, mean nest and air temperatures were computed for two periods only for each nest: 0000-0400 CST (a stable period of nocturnal air temperature) and 0600-1200 (representing daytime air temperatures that had the greatest daily variation). Daytime and evening data (12000000) were not used in this analysis because loggers were often in direct sun during part of that time and did not provide accurate air temperature measurement. Mean nest and air temperatures of the two selected periods and their coefficients of variation (CV) were used in a repeated measures ANOVA, in which the effect of clutch size, time of day, and age on nest temperature (T^sub n^) or coefficient of variation of nest temperature (CVT^sub n^) were analyzed. Because of a highly significant correlation of air temperature and nest temperature (P Acknowledgments.-This study was conducted at the Twin Cities Army Ammunition Plant (TCAAP), New Brighton, Minnesota, with the permission of the U.S. Army and Alliant Technology. We are grateful to Craig Andreson for establishment and maintenance of the bluebird boxes on the TCAAP property.
LITERATURE CITED
BLEM, C. R., AND L. B. BLEM. 1994. Composition and microclimate of Prothonotary Warbler nests. Auk 111:197-200.
BROWN, C. R. 1994. Nest microclimate, egg temperature, egg water loss, and eggshell conductance in Cape Weavers, Ploceus capensis. Ostrich 65:2631.
CALDER, W A. 1971. Temperature relationships and the nesting of the Calliope Hummingbird. Condor 73:314-321.
COOPER, J. A., AND A. D. AFTON. 1981. A multiple sensor system for monitoring avian nesting behavior. Wilson Bulletin 93:325-333.
DESTEVEN, D. 1980. Clutch size, breeding success, and parental survival in the Tree Swallow (Iridoprocne bicolor). Evolution 34:278-291.
DUNN, E. H. 1979. Age of effective homeothermy in nestling Tree Swallows according to brood size. Wilson Bulletin 91:455-457.
FLINT, P. L., AND IVI. C. MACCLUSKIE. 1995. A device for simultaneously measuring nest attendance and nest temperature in waterfowl. Journal of Field Ornithology 66:515-521.
HAFTORN, S. 1978. Egg laying and regulation of egg temperature during incubation in the Goldcrest (Regulus regulus). Ornis Scandinavica 9:2-21.
LOMBARDO, M. P., R. M. BOSMAN, C. A. FARO, S. G. HOUTTEMAN, AND T. S. KLUISZA. 1995. Effect of feathers as nest insulation on incubation behavior and reproductive performance of Tree Swallows (Tachycineta bicolor). Auk 112:973-981.
MARSH, R. L. 1980. Development of thermoregulation in nestling Tree Swallows. Condor 82:46-63. O’CONNOR, R. J. 1984. The Growth and Development of Birds. J. Wiley and Sons, New York.
PAYNTER, R. A., JR. 1954. Interrelations between clutch size, brood size, prefledging survival, and weight in Kent Island Tree Swallows. BirdBanding 25:102-131.
QUINNEY, T. E., D. J. I HUSSELL, AND C. D. ANKNEY. 1986. Sources of variation in growth of Tree Swallows. Auk 103:389-400.
October 20th, 2006
Sunday Times - Oct 15 10:14 PM
By Sy Lerman
All that was in tune for Moroka Swallows during their late 2-1 Premier League defeat against a lively Jomo Cosmos at Germiston Stadium on Sunday afternoon was the club’s entertaining brass band.
While the Birds only seemed to play with urgency and purpose while trailing, the young ensemble in the stand kept up an incessant musical rapport throughout the 90 minutes - but to no avail.
In the process, a mesmerising Dikgang “The Terminator” Mabalane pounced on Swallows’ periods of lethargy and loss of concentration to open the score in the 61st minute and then provide the winning goal for Cosmos in the 85th minute within seconds after Mame Niang had equalised for The Birds with a towering header.
Livelier and more purposeful, in the main, Cosmos deserved a success that keeps them on the heels of surprise log leaders Silver Stars. But Swallows will rue the fact that they were still seemingly celebrating their equaliser when “The Terminator” struck again with devastating effect in the 86th minute.
Cosmos had the ball in the net twice during the opening period but, much to the consternation of club officials on the bench, the goals were disallowed for off-side.
Then the Swallows players and officials were equally upset early during the second period when a spate of refereeing decisions went against them with the regularity of bullets fired from an AK-47.
Swallows seemed to play at three-quarter pace until Cosmos took the lead, with the Birds only then stepping up a gear to force their opponents back on their heels as the game developed into a frantic dog-fight.
However, the unrestrained joy among the 4,000 crowd that was dominated by Swallows supporters following Niang’s goal was speedily replaced by Mabelane’s unrestrained jubilation after scoring the winner, performing a series of acrobatic somersaults and then jumping into the arms of grateful and equally delighted coach Jomo Sono.
Sapa
October 19th, 2006
ecotravel.co.za
The Blue Swallow is an ambassador for a vital South African ecosystem namely grasslands. The South African grasslands form the major portion of our water catchment areas. More than 60% of the Grassland Biome has already been modified - forestry and agriculture playing largest roles. In South Africa only 2,23% of the Grassland Biome is formally conserved. The Grassland Biome is the least conserved, most transformed and therefore most highly threatened of South Africa’s 7 biomes.
The people of South Africa and the Blue Swallows are equally dependent upon the good management of the grasslands as “water factories”. The Blue Swallow is specialised to living in two grassland types in South Africa namely North-Eastern Mountain Sourveld and Natal Mist Belt. Of all the grassland types in South Africa in need of conservation, the two highest priority types are North-Eastern Mountain Sourveld and Natal Mist Belt. Both grassland types are located along the eastern South African escarpment in the Northern Province, Mpumalanga and KwaZulu-Natal.
As a globally threatened species the Blue Swallow, as a component of its unique grassland ecosystems in South Africa and Africa, should be viewed as the ambassador for the conservation of all of the other faunal and floral components and processes of its unique grassland ecosystem. Conserving the Blue Swallow will therefore result in the survival of other unique grassland species for which there is no working group and thus no conservation efforts.
South Africa is world-renowned for its biodiversity. Our grasslands are amongst the richest habitats for this biodiversity and are home to many fascinating endemic bird species, bird species only found in South Africa and nowhere else in the world. Birding is the fastest growing recreational activity in the world. The effective conservation of our bird-life will maintain unique birding areas that foreign tourists will visit and from which local communities will benefit. Protection of South Africa’s high biodiversity systems will be good for biodiversity, good for water quantity and quality, provide tangible benefits to local communities and be good for the Blue Swallow.
Current Conservation Status
The Blue Swallow is considered to be South Africa’s most endangered bird species (Brooke 1984). There are currently 81 known nests and a further 39 possible nests in South Africa and Swaziland. The numbers were obtained after extensive surveys conducted over the past fourteen years. Optimistically it may be possible to add a further ten nests once certain localities in the former Transkei and certain of the tribal trust-land areas in KwaZulu-Natal have been investigated for the presence of Blue Swallows.
An assessment for the total African distribution range of the Blue Swallow in 1985 listed it as near-threatened. By 1994 the Blue Swallow’s status had deteriorated and it is currently considered to be vulnerable (Collar & Stuart 1985, Collar et al. 1994). Since the 1994 assessment at least for South Africa and Kenya the species status has probably deteriorated from vulnerable to endangered (Nasirwa & Njoroge 1996). Countries for which information is minimal at this stage are the Democratic Republic of Congo, Zambia and Mozambique.
As a species of high conservation priority the Blue Swallow, as a component of its unique grassland ecosystems in South Africa and Africa, should be viewed as the ambassador for the conservation of all of the other faunal and floral components and the processes of its preferred grassland ecosystems. The Blue Swallow therefore ensures the long-term survival of other grassland species for which there is no working group and thus no conservation efforts.
Current global population
An optimistic assessment indicates that there are only 1500 breeding pairs of Blue Swallows remaining for their entire African breeding distribution range. The adult breeding population total is approximately 3 000 individuals.
A total of 89 definite and 34 possible breeding pairs are thought to occur in Southern Africa. An estimated 20 breeding pairs occur in Swaziland. In South Africa KwaZulu-Natal contains 51 definite and a further 19 possible nests, Mpumalanga contains 27 definite and a further 3 possible nests and the Northern Province contains 1 definite and a further 2 possible nests.
Elsewhere in Africa, numbers of breeding birds are estimated as follows: 300 pairs in the eastern-highlands of Zimbabwe, with another 100 pairs possible in adjacent Mozambique; 360 pairs in Malawi; 400 pairs in the southern highlands of Tanzania and 100 pairs in each of northeastern Zambia and southeastern Democratic Republic of Congo (DRC), respectively.
Large breeding populations of Blue Swallows currently in protected areas are Nyanga National Park (580 km²) in Zimbabwe (estimate of 200 breeding pairs) and Nyika National Park (3134 km²) in Malawi (conservative estimate of 260 breeding pairs) (Worsley pers comm., Holroyd & Quinni in prep).
Distribution range
The Blue Swallow’s global distribution range is limited to 10 countries in sub-Saharan Africa and is subsequently an intra-African migrant (Turner 1989). It breeds in KwaZulu-Natal, Swaziland, Mpumalanga, Northern Province, eastern Zimbabwe and adjacent Mozambique in southern Africa. In east Africa the Blue Swallow breeds in Malawi, north-eastern Zambia, south-eastern part of Democratic Republic of Congo and south-western Tanzania (Turner 1989). The birds arrive at their breeding grounds in South Africa and Swaziland towards the end of September (Parker 1994), and depart again in mid-April (Keith et al. 1992). From throughout their breeding range the Blue Swallows migrate in the non-breeding season to Uganda, western Kenya, north-eastern part of Democratic Republic of Congo and possibly also north-western Tanzania in central Africa but do not breed there (Earle 1987).
The furthest north that a Blue Swallow has ever been recorded is Kidepo Valley National Park that has its north-western boundary on the border between Uganda and Sudan in the north-eastern part of Uganda (Butchard 1996). The Blue Swallow range states are Democratic Republic of Congo, Uganda, Kenya, Tanzania, Malawi, Zambia, Zimbabwe, Mozambique, South Africa and Swaziland.
Habitat
The Blue Swallow prefers high altitude, high rainfall (> 1000 mm p.a.), undulating, open, primary mist-belt grasslands (Allan et al. 1988). The preferred sour grasslands generally have a sward height of < 0.5 meters. The Blue Swallow ecosystem throughout its breeding range in Africa is characterised by the occurrence of mist, during the birds breeding periods. In South Africa and Swaziland the bird is specialised to and therefore only found within the two grassland types known as north-eastern mountain sourveld and Natal Mist-Belt (Acocks 1975). Natal Mist-Belt is the grassland type in which the Blue Swallow is found at the southernmost limit of its African distribution range - KwaZulu-Natal in South Africa. From information published in 1967 the grassland type in which the Blue Swallow is found in Zimbabwe, Mozambique, Malawi and Zambia appears to be similar to the grassland type known as North-Eastern Mountain Sourveld in South Africa and Swaziland (Wild et al. 1967). At this stage the grassland type in which the birds are breeding in Tanzania and the Democratic Republic of Congo is believed to be similar to that of their range in Zimbabwe, Mozambique, Malawi and Zambia. As yet no information could be obtained on the grassland composition or type that the birds inhabit in north-western Tanzania. In South Africa North-Eastern Mountain Sourveld contains 130 endemic plant species and Natal Mist-Belt contains 51 endemic plant species.
The two grassland types in urgent need of conservation in South Africa are North-Eastern Mountain Sourveld and Natal Mist Belt (Duthie 1994; Low & Rebelo 1996).
Nest, Eggs and Nestlings
Blue Swallows construct a cup-shaped nest out of a mixture of mud and grass. The nest is attached to the wall of natural or artificial holes. Natural holes currently used by the birds are natural sinkholes and Aardvark burrows or artificial sites such as abandoned mine shafts. The birds prefer holes with an overhang under which the nest is constructed so as to protect the exposed cup from the wind and rain. Nests in suitable nest sites are often repaired each breeding season and used over many seasons. Both the male and female contribute to nest building or repair. The female carrying out most of the work.
Two to three eggs are laid at 24 to 48 hours between each successive egg. Only the female incubates the eggs for 14 - 16 days. The female incubates the nestlings. Both the male and female feed the nestlings. At the peak of their development the adult birds arrive at the nest with food for the nestlings at a rate of once every 2 minutes. Nestlings fledge 20 to 24 days after hatching and remain in the nest area for two to three weeks during which time the parents continue feeding them. The nestlings gradually begin feeding themselves during this period. When conditions are favourable Blue Swallows are double brooded, certain pairs being capable of raising two sets of nestlings in a single breeding season. Adverse weather conditions as a result of mist and rain often result in Blue Swallow eggs not hatching or nestlings not fledging (Evans & Bouwman 2000). In some seasons this seriously affects breeding success. Fiscal Shrike has been recorded predating both Blue Swallow eggs and nestlings.
Threats
The major reason for the reduction in surface areas and fragmentation of these two grassland types and the concomitant endangered status of the Blue Swallow has largely been as a result of commercial forestry for the timber, pulp and paper industry (pine, eucalyptus and wattle plantations). The high altitude, high rainfall, mist-belt grassland areas that are characteristic Blue Swallow habitat are unfortunately also highly suited for the commercial cultivation of these exotic trees. In Zimbabwe the borders of Nyanga National Park are easily found as wattle and pine plantations have been planted right up to the edge of the park. Private ownership of the mineral rights to most of the Blue Swallow localities in Mpumalanga represents a current and potential future threat (Evans 1996). Increased tourism activity and development has resulted in the loss of Blue Swallow breeding pairs in the Mac Mac and Graskop Townlands area. This highlights the need for careful consideration and proper planning of tourism ventures (Evans 1997). Other reasons for the decline in and vulnerable status of the Blue Swallow and its grassland habitats are habitat destruction and fragmentation due to potato, maize and sugar cane cultivation, road construction, overgrazing and inappropriate annual burning of grasslands to improve grazing potential. The annual burning of grassland types that should be burnt every two to three year’s results in a drastic decrease in overall biodiversity. A factor resulting in a reduction in the breeding success of Blue Swallows in certain breeding areas is disturbance of the birds at the nest by the young boys herding the cattle on tribal grazing lands (Boycott pers comm).
Conservation
Due to the migratory nature of the Blue Swallow it is necessary to focus conservation action, advocacy and monitoring over its entire distribution range. Conservation activity should be aimed at preventing the status of the Blue Swallow from deteriorating further. This is achieved by working at resolving conflicts between the requirements of the Blue Swallow and the factors threatening the future existence of those requirements.
The Blue Swallow is listed on both Appendix I and II of the international Convention for the Conservation of Migratory Species of Wild Animals (CMS).
Protected Areas, Natural Heritage Sites and Important Bird Areas
Malolotja Nature Reserve (IBA SW001) in Swaziland and Impendle Nature Reserve (IBA SA077) in KwaZulu-Natal are the only formally protected areas holding breeding Blue Swallows; with totals of eight pairs each. Another 22 breeding pairs of Blue Swallows are protected in six Natural Heritage Sites; three in Mpumalanga and three in KwaZulu-Natal. The KwaZulu-Natal Mistbelt Grasslands (IBA SA078), a series of disjointed grassland patches in a farmland mosaic, hold 38-55 Blue Swallow breeding pairs (Johnson et al. 1998). The nine breeding pairs in the Blue Swallow Natural Heritage Site (IBA SA014) in Kaapsehoop represents the highest breeding density for South Africa (1 pr/52 ha) (Allan et al. 1988). The Graskop Grasslands (IBA SA011) and Misty Mountain Natural Heritage Site (IBA SA013) hold 14 and 2 breeding pairs of Blue Swallows respectively. Blyde River Canyon (IBA SA010) contains a single breeding pair with the possibility of a further pair.
October 18th, 2006
accessmylibrary.com
Author: Harrison, George H.
Source:Â Birder’s World
COPYRIGHT 2004 Kalmbach Publishing Company
One swallow maketh not summer,” wrote the English playwright John Heywood in 1546, but for me, one swallow, the first Barn Swallow of the season, made it summer at my Grandfather Hill’s farm near Leisureville, Pennsylvania.
I spent many of my boyhood summers at the Hill farm doing chores and learning about nature. I put up bluebird houses, spied on a den of red foxes, chased cottontail rabbits, found the nest cavity of a Red-headed Woodpecker, and kept box turtles from the woodlot. But one of the most fascinating lessons for me was watching the Barn Swallows that nested on the rafters of the barn.
I can still see in my mind their flowing, graceful flight. Like performers in a choreographed ballet, they skimmed over fields, swooped down on ponds, and darted effortlessly through the barn door and up to rafters where mates and young awaited. As they flew, they chittered and chattered a pleasant chorus of kvik-kvik, wit-wit. When they arrived at the nest, there was a chatty greeting between mates or a demanding chorus of begging chicks.
Little did I know then that I would grow up to admire the beautiful forked-tailed bird with a metallic blue back and rich rufous breast far from the Pennsylvania farm. That’s because the same species, Hirundo rustica, is found on all the continents except Antarctica. I’ve had the pleasure of watching Barn Swallows in the Cotswolds of England, on the beaches of Normandy, in the Steppes of Russia, and on the Serengeti in East Africa.
I have met farmers all over the world who have a kinship with Barn Swallows because…
October 17th, 2006
.wild-bird-watching.com/
The Barn Swallow, with its distinctive long forked tail, makes it the easiest of North American swallows for bird watchers to identify. Although in flight the feathers are swept back and form a single long point behind the bird.
One sure sign of summer for anyone who enjoys bird watching, is this bird flying back and forth to any open barn or outbuilding in the country. This bird spends more time in the air then almost any other land bird.
Description
Measuring 5 1/2 to 7 inches in length with pointed wings and a deeply forked tail.
The bill is very short. Dark blue-black above with a dark rusty throat. The rest of the underparts are a buffy or pale rusty.
Mating Habits
Swallows are generally monogamous, males mating with a single female. Although rare, males sometimes will
pair with 2 females.
Paired males will aggressively defend the small area around the nest, and guard his mate from other males that might attempt to copulate with her.
Nesting Habits
Both the male and female bird build the nest, usually in the morning, making up to 1,000 trips to collect mud.
Although this bird originally nested in caves and on rocky cliffs, the barn swallow was quick to take advantage of man-made structures. Today, these birds nests only in association with man-made structures.
The nest is a cup of mud pellets lined with grass and feathers, built under eaves of buildings, resting on a beam, or some projection in barns, under bridges, in culverts, or occasionally in niche on a cliff.
The female lays 3 to 8 white eggs that are spotted with reddish brown. The eggs are incubated for 14 to 16 days and the young will leave the nest in 18 to 23 days.
Two broods a season may be attempted.
Feeding Habits
These birds feed on flying insects and feed on the wing. During the breeding season these birds will feed in pairs and fly at a low altitude, generally over fields and water.
During the non-breeding season they will feed in small, loosely formed flocks.
Habitat
Bird watchers can look for Barn Swallows in open country and marshes, especially near barns, outbuildings, bridges, and culverts.
October 17th, 2006
oldandsold.com
fly-killing. But how did so many flies get in here?” “Oh, someone left the screen door open,” I replied; “that is one reason, and, since you have mentioned swallows, you remind me of another, and that is that we haven’t swallows enough to catch all these flies. If they were as common as they used to be, I don’t think there would be so many flies to bother us.” “Did they use to be very plenty?” inquired Ned. “Yes,” I said, “according to all accounts the familiar kinds were quite abundant up to about twenty years ago, when the hateful English Sparrow drove them away by fighting them or taking their nests. I remember well when I was small what lots of swallows there were around Boston, where I lived, far more than there are now. Of course I don’t mean to say that there weren’t any flies then, but there was a big colony of Barn and Eave Swallows on our next door neighbor’s barn, and with such a swarm catching flies all day about our place you couldn’t make me believe that there were not less flies than there would have been without them.”
“Don’t they catch other insects beside flies?” asked Ned, becoming evidently interested. “Yes,” I told him, “they are great on mosquitoes and about every sort of small flying insect. The Government ornithologists of the Biological Survey say that in the South swallows feed upon the dreaded boll weevil, and they are getting up a crusade to try to protect the swallows and introduce them to regions from which they have been driven out. One good method is to kill off the English Sparrows around their colonies, and also to put up suitable boxes for the kinds that use them. Of course boys ought not to disturb them, and the owners of barns where they build should welcome them, even though they make some dirt to clean up. They are well worth any trouble they may cause.”
After this little talk about swallows, Ned helped me drive out the flies so that there would be none of them on my bird article, and I went to work again in peace. Besides helping me in this swallow-like occupation of chasing flies, Ned promised to go with me that afternoon and help me photograph a nice Barn Swallows’ nest with four nearly fledged young, which were now about to leave.
It was a pretty hard proposition, Ned thought, when he saw the nest, on the projecting end of a timber inside a barn, away up under the roof where it was quite dark and almost inaccessible. However, I thought there was a way. We got a long ladder, and I climbed up on a beam which went rather near the nest. I pulled the ladder up after me and placed it across two beams. Then Ned handed me up some boards and I made a little platform on the- ladder to stand the camera and tripod upon. The camera set up on the tripod could now stand close to the nest, but it was too dark even to focus. However, I was ready for that difficulty. I had brought a good-sized mirror, and now I asked Ned to stand just outside the barn door in the strong sun-light and throw up the reflected light upon the nest. It was easy now to focus. Then I held up a smaller mirror which I carried in my pocket and had Ned throw the light on my mirror, and I in turn threw it down into the nest upon the backs of the young birds, and thus I made some successful quite short exposures. Then I brought down a young swallow, posed and photographed it outdoors, put it back into the nest, and the work was done, and well done—thanks to my valuable assistant.
Probably the Barn Swallow is the best known of the six species found in our Northern and Eastern districts —the bird with the forked tail, reddish breast and shiny blue-black upper parts. They build nests of mud and straw on beams inside barns and sheds. The settlement of North America by the white man has changed the habits of many of the birds, notably the swallows, and among them this particular kind. Its original preference was for rocky caves as a nesting site. Just once in my life have I found a nest thus situated. It was in a cave on lonely Seal Island, which lies twenty miles off the rugged coast of Maine, in Penobscot Bay.
Our Barn Swallow is such a happy, friendly bird that nearly everyone who knows it loves and admires it. We enjoy its merry twitterings as it darts about the barn, and are pleased at the grace with which this greyhound of the air doubles and turns. When we go out for a drive, it is a pretty sight to see them circle about us, catching the insects which our advance starts from the grass or weeds along the country roadside.
Perhaps next in familiarity comes the Eave or Cliff Swallow. This is the other kind which frequents the barns. I builds bottle-shaped nests of mud pellets up under the eaves, which are often clustered thickly together and partly built one upon the side of the other. In the primitive days these colonies of nests were built on cliffs, and in some parts of the West they are built there even yet. So the bird is the genuine Cliff Swallow out there, and the Eave Swallow with us. Originally there were no Cliff Swallows where there were no cliffs, but with the country’s settlement they spread nearly everywhere, and the dates are on record when they first appeared in various localities. This bird looks quite different from the Barn Swallow, and can be told by its nearly square tail, the pale reddish patch at the base of the bill and on the upper rump, and the light underparts.
I have photographed the nests by putting up a ladder under the eaves, driving my screw bolt into the side of the barn, screwing the small camera to it and making long-timed exposures, since the nests are in the shade. To get the adult birds from life, I await quietly beneath the nests on some low barn, with my reflecting camera in hand, and snap the birds as they fly to their nests. When the young are just beginning to fly they are quite tame and one can often walk up close to them with the camera.
The nests of many swallows get very lousy, like the Phoebes’, and it was owing to this that I once had a rather severe punishment for meddling with the Eave Swallows when I was a boy. I wanted some swallows’ eggs, and, after climbing up to some nests by means of a ladder, was trying to get my fingers into the narrow entrance of one of them, when down came the nest and smashed all over my bare head. In a moment I was swarming with bird lice from head to foot—and what a time I did have! It was days before I got rid of them all, and I was sore in every member from their bites and my scratching. Fortunately it was vacation time, and I was able to keep aloof from most of mankind.
Then there is the Tree Swallow, the kind with the pure white breast and glossy steel-blue back. How they used to swarm on the marshes and on the telegraph wires, when I was a boy, in August when they were getting ready to migrate ! But now their numbers seem pitifully small in comparison. Originally they nested in cavities of trees. Then, in well settled, localities, they changed to the bird boxes which kindly disposed people put up for them. But the English Sparrow came and drove them out, and now they have gone back to the hollow trees again.
Out in North Dakota, I have seen pairs of them flying in and out of hollows in low trees along the shores of rivers and lakes, and I was wishing that I had taken the time to photograph them. So it was pleasant to me to find a colony of them near my home nesting in stubs in the overflowed woodland where I have told of the woodpeckers nesting so abundantly. Some of the stubs which they had chosen stood out in pretty deep water and the holes were rather high up. I was standing on the “corduroy” roadway across the swamp and wondering how in the world I was going to work it to get some pictures, when I saw a Tree Swallow fly into a hole near the top of a low stub only about five feet from the water, the stub being only a yard out from the road. I waited two weeks or more till the young were hatched, and then with my reflecting camera and a lot of plate holders, I paid a visit to the nest. The male bird sat on a low branch of another stub, quite near the nest hole, and let me walk quietly up and snap him. He flitted to another stub and I got some more pictures of him. Meanwhile the female flew to the nest with a fly, so I sat down on the edge of the roadway partly behind a bush, with the camera on my knees, aimed at the nest. For a few minutes the birds flew about twittering, excited by my presence. But I sat still, and presently the male ventured. I snapped him as he approached the stub, and he flew back without entering. But in a moment he alighted at the entrance with a fly, and, not heeding the sound of the shutter, entered, fed the young, and emerged carrying. a sac of excrement. By this time I had changed the plate and caught him as he left. Then the female came, and they were constantly going and coming, giving me all the snapshots I wanted. Later, when the five young were about ready to leave, I took out two of them and posed them, and then put them carefully back into the hole.
One day I came out from the woods on the adjoining hill, hundreds of feet above this morass, overlooking the whole tract. It was a lovely panorama of high rolling hills, with two lakes nestling in the valley, and, aided by my strong field glass, I actually could see the old woodpecker hole in the swallow stub, and see the swallows enter and leave the cavity as they fed their young.
Still another familiar species is the Bank Swallow, the small brownish fellow that digs out burrows in gravel banks near ponds or streams. They are quite common, and a number of banks or cuts in my neighborhood each boast of a little colony of a dozen or more pairs. The birds arrive toward the end of April, and presently go to work digging their burrows, and then make trips to poultry yards to pick up feathers with which to make soft lining for the nests, that the very fragile pure-white eggs which are to be deposited may not be broken.
One day I visited a colony situated in a gravel cut, just off a main road. The burrows were not deep, and from one of them I took out a parent bird which was incubating, having previously set up my camera focused on a hole, and, placing it at the entrance, secured a snapshot before it escaped. Meanwhile I had allowed the horse to graze by the roadside unhitched, watched over by Ned. Just ahead there was a rise of ground and a turn in the road. I had not thought about the possibility of an automobile coming along, but, as luck would have it, one came just then, going at very moderate speed. Before I could get back the horse broke away from Ned, shied into the fence, and then dashed off with the shafts, leaving the rest of the vehicle hung up. The animal only ran to the next farmyard, where it stopped and was caught. The driver of the machine was a gentleman. He stopped, proffered assistance, gave his number, and so on. Though I was out a buggy, I did not sue him, as he had been so polite, and I was at fault for leaving the horse as I did. But the country roads are very narrow, and these engines put residents and visitors in the country in jeopardy of their lives. It is not only ill-mannered, but lawless and criminal for anyone to invade country roads with an automobile and not drive with the utmost care, stop when he is asked by the driver of a horse, and in every way be considerate, in view of the peril to life and limb which he is creating. Machines are impracticable in the country for at least half the year, and people living there are compelled to keep horses. Were all autoists gentlemen like this one just mentioned, people in the country would not be put to as much inconvenience and danger as at present they suffer, many, especially women and children, being afraid to drive or ride out, and thus are compelled to stay at home.
There is another swallow, similar in appearance and habits to the Bank Swallow, which is not so well known —the Rough-winged Swallow. They, are not often seen north of the Middle States and are common only in the West. At a distance they are distinguishable from the Bank Swallow mainly by being a little larger and having uniformly dark under-parts. Frequently they nest on the timbers under bridges, or in crevices of abutments, although they also nest like the Bank Swallow. Even Audubon did not distinguish them from Bank Swallows until he happened to shoot some specimens. So it will be well to watch for them among the supposed Bank Swallows, and some day we may add this rather rare bird to our list.
Some people call the Tree Swallow the Martin, but the genuine Martin is the Purple Martin, a larger species, the male of which is entirely of a dark glossy steel-blue color, the female duller, and paler below. They are beautiful and useful birds, but unfortunately are very tender, and late cold storms, combined with the attacks of the English Sparrow, have almost exterminated them in the New England States. In populated regions at present they generally breed in bird-boxes which people are glad to prepare for them. Sometimes, after prolonged cold rain storms in June, whole colonies of Martins, old and young alike, have been found dead in their nesting boxes. I never see them now except as migrants. Their original manner of nesting was in hollow trees, like the Tree Swallow. Out in the Turtle Mountains of North Dakota I once found them breeding quite plentifully in the poplar timber, and took a picture of a pair of them as they alighted on the branch of a stub near their nest cavity, an old woodpecker hole.
We have just one more bird to tell of in this chapter, the one that people persist in calling the Chimney Swallow. In general appearance and habits it is swallow-like, but in structure it is quite different, and belongs to the family called Swifts. So let us get used to calling it by its right name, Chimney Swift, and be accurate.
Its feet are so weak and cramped that it does not perch, but clings to a perpendicular surface, such as the inside of a chimney or a hollow tree, propping itself from behind with its peculiar tail, each feather of which ends in a sharp spine or spike. But in flight it is master of the situation, and well deserves its university degree of Swift. Almost ceaselessly, oftentimes by night as well as day, it is awing, tireless in pursuit of flying insects. It has been estimated that each swift flies a thousand miles every day, yet it never seems to weary.
Under primitive conditions, before the settlement of the country, the swift resorted to hollow trees for rest, shelter and nesting. But now it seldom occupies any other retreat than a chimney. In the autumn, when flocking preparatory for its migration south, I have seen assemblages of them at dusk drop into some selected chimney in a steady stream, until thousands must have been clinging to every available inch of brick inside.
They return to us about the last of April, but are late in nesting, for ordinarily the eggs are not laid till July. During June they may be seen darting over the dead tops of trees, hardly pausing an instant in their flight as they grasp and wrench off a twig. Having secured one, the bird takes it down the chimney and sticks it to the brick wall with gummy saliva, which she ejects. This is continued till the curious basket like structure has been completed, and then four or five elongated pure white eggs are laid. Many accidents occur. Rains wash down the nest, or the young fall down into the fireplace or pipe below, where they are likely to be left to starve. The brood of swifts make considerable racket, and the descent of the old birds into the chimney causes a rumbling sound like distant thunder. They drop a good deal of dirt, too, down the chimney. But they amply pay for their misdemeanors in the multitude of flies and mosquitoes which they destroy,
It is a hard matter to photograph a nest, owing to the narrowness of the chimneys. But I was fortunate in happening upon a very peculiar nesting site. A pair of swifts chose to build in a barn. Up near the top of the hayloft, near an open window, for the past three years they have stuck their curious nest to the plain board wall inside. The first year they raised but one youngster and the next season four. The third season they built the nest, but for some reason did not lay the eggs there.
I photographed this nest in the same way that I photographed the young Barn Swallows, with the help of Ned, the ladder and the mirrors. The second year I paid my visit when the young had just crawled from the nest and were clinging to the boards near it like so many bats. One flew off, but I photographed the other three, and then put one back in the nest and took a picture of it there. After that I carried one outdoors in the light and took some pictures showing in detail how they cling and brace themselves with the tail.
A pair of them build every year in one of my chimneys, and this year, for some reason, the eggs did not hatch. Ned wanted to get them as curiosities, so he made a small scoop net at the end of his butterfly net pole and succeeded in landing the nest and two out of four of the eggs;
A well-known naturalist once told me that it seemed to him that the swift in flight used its wings alternately. It would be an interesting bit of sport and scientific research combined to secure a series of flight pictures of the swift and try to find this out. I have thought that sometimes I would squat on the ridge pole by some favorably located chimney to which swifts resorted and see if I could get some pictures. Who else will try it?
October 16th, 2006
The Daily Gamecock - Oct 05 9:17 PM
Professor tells students about studying radiation at site of nuclear disaster
By: Gina Vasselli
A professor shared his experience studying the effects of nuclear radiation on ecology with students Thursday.
Tim Mousseau, a biology professor and the associate dean for research and undergraduate education at USC, shared the results of his research on barn swallows, a small bird, in the area surrounding Chernobyl.
In 1986, a nuclear power accident occurred at Chernobyl in the former Soviet Union, now the Ukraine. The accident caused high-level radiation to spread over a 20-mile radius.
Mousseau studied barn swallows in areas around Chernobyl and tested to see the effects of long-term radiation on the ecosystem. He studied the DNA fingerprints, sperm and breakage of chromosomes in the swallows.
“We found that mutation rates at the DNA level were two to 10 times the mutation rates in control areas, and this was in medium contamination areas,” Mousseau said.
Mousseau’s study was one of the first that studied one animal intensely for the effects of the radiation.
Mousseau said he was surprised at some of the indicators of nuclear radiation that popped up, even when they weren’t looking for them.
He told a story about how the group went looking for barn swallows close to the contamination area and found a barn that had nests for 300 to 600 pairs of barn swallows.
But they found that only five pairs were still using that area for nesting. Because barn swallows return to the same place year after year to nest this suggested to Mousseau that many of the birds had died.
The final results of Mousseau’s studies showed that the survival rate for the swallows in the Chernobyl area was less than 15 percent. In a control area in the Ukraine, the survival rate was 40 percent.
Mousseau had experiences with the contamination that people in the area were exposed to daily.
Mousseau said he tested the fruit and vegetables that a local farmer gave to the group and found that they were contaminated, with the berries and mushrooms being the “hottest.”
“These people are being exposed every day to significantly high doses,” Mousseau said.
People have been allowed to move back into the area because the area seems to be returning to normal Mousseau said.
Mousseau stressed that science does not know the effects of the radiation on the population, including animals and humans, because they have not studied it yet.
“We’ve put no money into it,” Mousseau said. “We need to invest more into this kind of research.”
There is a big difference between slow, long-term exposure, like that at Chernobyl, and the pulse of high-level radiation, as during the explosion of a nuclear bomb, Mousseau said.
Low levels of radiation over a long period of time do not cause a single kind of cancer or mutation but “a whole slew of consequences,” Mousseau said.
Mousseau said that before countries decide to use nuclear power they should invest money into researching the consequences associated with nuclear waste and nuclear power.
October 16th, 2006
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