Features of nesting of the shore swallow

The shore swallow (Riparia riparia L.) belongs to the genus Shore swallows (Riparia Foster) of the Swallow family (Hirundiniada). There are 5 species of this family in Russia.

The shore swallow is not much different in body shape from other swallows. The dorsal side of the female and male is brown, the ventral side is dirty white, with a wide grayish-white transverse stripe on the crop and chest. Chicks and adult birds have similar colors, there is no sexual dimorphism. They are smaller in size than other swallows: the length does not reach 140 mm, and the weight is 14 g. The tail is not deeply cut.

It makes nests in steep banks of rivers, streams, and ravines. Prefers southern and southeastern exposure. Digs holes, choosing the loosest layers. Swallows' food consists of flying insects.

The shore swallow is distributed throughout the world, except in the coldest latitudes and oceanic islands.

In Europe it lives everywhere except the northernmost capes.

In Asia, the northern border of the range goes from the upper reaches of Lozva to the mouth of the Ob and the Ob Bay, crossing the Yenisei at 70 degrees north latitude, the Lena, Kolyma at the delta and goes to the mouth of the Anadyr, capturing Kamchatka and the Kuril Islands. The shore swallow is widespread throughout Altai and the adjacent plains.

There are six subspecies of the shore swallow. Subspecies differ in size, shades of overall color and the presence of light edges on the back feathers.

The pale subspecies inhabits Northwestern Altai, found near Biysk.

On the Ob, the dark subspecies reaches up to Barnaul.

The shore swallow is a species that brings great benefits to agriculture and forestry. The range of food is quite diverse; it contains representatives of ten orders and twenty families of insects, of which about 80% are pests, as well as a small number of spiders. According to the results of a study in the Oksky Nature Reserve N.R. Pavlova (Pavlova, 1962)6 the average destruction of harmful insects is 76%. Although it is known that there are numerous colonies on the right bank of the Biya in its lower reaches in the vicinity of the city, currently no such information has been found on the location of bank swallow colonies. Observations were made of three colonies of bank swallows located 100-200 meters from each other on the right bank of the Ob River, five kilometers from the confluence of the Biya and Katun rivers in the vicinity of the village of Fominskoye.

The village of Fominskoye is located 15 km away. from the city of Biysk in the central part of the Altai Territory, in the southeast of the West Siberian Plain. Its coordinates are 52( 30(( N, 84( 55(( E, 160 meters above sea level.

The village of Fominskoye is located in a temperate climate zone, continental type with a clearly defined change of seasons. A noticeable influence on the climate is exerted by air masses coming from the depths of the continent - from the south, east and west. Warm tropical air comes from the south, cold continental air comes from the east. Atlantic air from the west arrives greatly transformed. In summer it creates humid and cool weather, in winter it creates humid and warm weather.

The longest day in June is more than 17 hours. Summer is slightly cloudy, with an average cloudiness of 5.7 points. Average temperature in June – 25, July – 29, August – 21.

This area is characterized by sufficient moisture in the summer. In summer, droughts are common, which are associated with the formation of a stable anticyclone; dry winds and dust storms are frequent. On average, 560-570 mm of precipitation falls per year. The maximum amount of precipitation occurs in summer June - August.

There are significant pressure fluctuations in summer and winter. In summer, due to the strong heating of the surface, warm air rises and the pressure becomes low. For July, the average pressure is 754 mm.

In the village there are winds from all directions. The most frequent winds are from the southwest.

The average flood of the Ob River occurs on May 9, the water height during the flood is four meters or more.

The soils are predominantly represented by sandy loams and rarely light loams, the soil-forming rocks being sand.

The vegetation of the village is represented by sparse forest, wasteland plants - nettle, quinoa, wormwood and thickets of wild sea buckthorn, pastures and meadows used for mowing and grazing.

LITERARY REVIEW

The material available in the literature about shore swallows is both faunistic in nature and also reveals issues of nesting life.

Recently, scientists have been recording the initial state of the avifauna and conducting complete censuses of birds in zoogeographical terms. Materials on the biology and ecology of birds are summarized for the purpose of their protection, reproduction and rational use.

A description of the shore swallow for all zoological areas of Altai was given by P.P. Sushkin. Its two subspecies R.riparia and R. Dulita, according to the researcher, inhabit different areas. The subspecies R.riparia is characteristic of the Western outskirts (Western Altai, the Alei river, the vicinity of Ust-Kamenogorsk), the second subspecies R.dulita inhabits the rest of the North-Western Altai and was found near the city of Biysk.

The wide distribution of the shore swallow in Central Siberia, the number of colonies, and their numbers in the studied areas are described by E.V. Rogacheva.

Y.S. Ravkin, recording the initial state of the avifauna, conducts surveys of the shore swallow in the forest zone of the Ob region and North-Eastern Altai and provides data on the number of birds during nesting and timing of arrival.

The study of nesting features of shorebirds was carried out on the territory of the European part of the USSR.

N.R. Pavlova studied the reproduction of the shore swallow in the Oksky Nature Reserve. Material was collected on the nesting period, the process of laying eggs, hatching of chicks, growth of chicks and development of plumage was monitored. The species set of food and nutrition of chicks of different ages were studied.

R.N. Chernichko, studied the dependence of the reproductive success of the shore swallow on some characteristics of the colonies, and found that the greatest reproductive success is observed in large colonies located in loamy soils, while the reproductive success does not depend on the horizontal distance of the burrows from the center of the colony. Nesting success affects the spatial and ethological structure of colonies. Further research by R.N. Chernichko is devoted to the study of the patterns of territorial connections of shore swallows, as well as the metric characteristics of this species.

Observations of reproductive ecology conducted by V.S. Shkarin and L.P. Marx in the south of Western Siberia (Novokuznetsk district of the Kemerovo region) revealed the features of the nesting life of shorebirds: timing of arrival and laying of eggs, clutch size, hatchability of chicks. Features of postembryonic development are noted.

Researchers believe that many issues regarding the nesting characteristics of shorebirds have not been sufficiently studied and may have their own characteristics, depending on the nesting area of the birds. The description of the nesting life of the shore swallow found in the literature is quite contradictory.

APPEARANCE OF BIRDS

The birds caught on July 3, 2004 are adults. The color of the back is brown, the tips of the feathers are reddish (1mm), the throat, crop, and belly are pure white, the tail notch is small. The beak is black, the legs are short black, the toes are located 3 forward and 1 back. There are small white spots in the color of the flight feathers of the wing. Bird sizes: body length 12-14cm, wing length – 14cm. The appearance of the birds corresponds to the description of the species - shore swallow.

SPATIAL STRUCTURE OF COLONIES

Observations in 2004 showed that the first colony has a length along the bank of 26 m, a cliff height of 3-4 m, and is located 0–7 meters from the water, depending on the river water level. There are 286 burrows in the colony. This section of the coast is washed away during floods and partially collapses. Previously used for economic purposes, which explains the distribution of soil layers. It contains 4 layers: peat (10-30 cm), black soil (20-60 cm), clay and sand (70-200 cm), black soil (30-60 cm).

The burrows are located in the first two or three layers, mainly in sand and clay in the western (peripheral) and black soil in the eastern (peripheral) parts. According to village residents, the colony has existed since 1994. At the time of observation, the colony was inhabited by 81 minks. Measuring the location of occupied burrows showed that the average distance between occupied burrows was 15.3 cm. Birds prefer to populate the western (peripheral) – 45 nests and the central – 48 nests parts, while the eastern (peripheral) part is inhabited worse than 39 nests, which is confirmed by observations in 2005. Currently, the colony is not subject to anthropogenic influence. In 2005, the population of the colony increased and amounted to -124 minks. The total number of minks decreased to 163. This was caused by the collapse of the bank during the flood by one meter.

The second colony is located 120 meters from the first and occupies 24 meters of bank, 6 meters high, located 1-3 meters from the water, depending on the water level in the river. In 2004, there were 110 minks in the colony, of which 40 minks were inhabited. The soil section has 2 layers: chernozem (20 cm), the second layer is a mixture of clay and sand (150 cm). The burrows are dug in the sand at a height of 40-60 cm from the upper edge of the shore. According to my observations, the year of settlement is 2000. in 2005, the population of the colony increased and amounted to 60 minks. In 2005, birds were busy building new burrows, so the total number of burrows increased from 110 to 130.

The third colony, located 200 meters from the second, is the youngest, according to my observations, formed in 2001. Its length along the coast is -21 m, the height of the coast is 8 m, located 1–3 meters from the water, depending on the water level. In 2004, the number of burrows was 120, occupied - 50. In the soil section, 2 layers are visible: chernozem (20 cm) and the second layer is a mixture of clay and sand (200 cm). The burrows are located in the sand at a height of 40-60 cm from the top edge of the cliff. In 2005, the size of the colony increased and amounted to 70 inhabited burrows, the total number of burrows did not change. Despite the collapse of the bank during the flood, the shorebirds dug new holes.

Observation of the colonization of burrows of the second and third colonies confirmed that birds, when settling, give preference to the peripheral (western) and central parts of the colony. There was no difference in the burrow colonization of the upper and lower burrows. No anthropogenic influence on sand martin nesting has been noted.

The edaphic factor plays an important role in the success of reproduction. Every year, all three colonies are subject to collapses and landslides during floods, due to the erosion of the coast by water from below. Despite this, birds willingly colonize sandy and loamy soils, but are reluctant to settle in black soil.