Saturday 27 February 2010

Processionary caterpillars sighted at Asomadillas

(By e-mail) "My name's Sarah Spencer and I've been in Jimena for 2 years now. This morning while walking my dogs at the Asomadillas pine forest we spotted A LOT of processionary caterpillars. Please could you post a warning on Jimena Pulse to alert dog walkers and families not to go to any ares where there are pine trees? If you could also pass the information on to Tio Jimeno too, that would be great." More about this dangerous (we mean the bugs, not our Spanish colleagues) pest>
(From WildSide Holidays) The pine processionary caterpillar (Thaumetopoea pityocampa) is known as ‘procesionaria del pino’ in Spanish and during late winter/early spring they will be coming out of the trees and forming conspicuous snakelike lines as they traverse the ground searching for soft soil to burrow into. They will not be far from a pine tree, but that does not mean that you will only see them in large pine woods, they are just as likely to be found in urbanisations and road side plantings wherever pine trees are present.
There are several stages within their lifecycle but they are only dangerous to people and pets during the caterpillar phase. In the adult phase they are a simple and unremarkable, short lived moth which emerges in the summer and flies at night. The male moth is attracted to the female moth by pheromones that she emits. They will mate and a single female can then lay up to 300 tiny eggs which she attaches in a mass to a pine needle. Around one month later these eggs hatch into minute caterpillars. These larvae have 5 growth stages that are called “instars”.  They grow quickly in body size, moult their skin and that denotes the start of the next instar.

These social caterpillars living in family communities eat pine needles by night and sleep in little temporary silk nests by day. At this point they are nomadic and the nests are not really visible. However at the third instar (moult) the siblings build a permanent white silky nest on the tip of a pine branch. These appear during the winter as white cotton or ‘candyfloss’ like structures and a single pine tree may have many. If there are half a dozen or more in the top of a tree they can easily strip the leaves with their nightly foraging, possibly clearing all greenery off some branches and in many cases damaging the tree badly.  By feeding under the cover of darkness they avoid attack by birds and predatory wasps. At dusk the caterpillars leave their communal nest in search of food, there is no single entrance hole, they simply push through the silk layers and once onto a branch they will leave a scent trail to help themselves find their way back before the morning light arrives.

This period of night time eating occurs during the winter months and whilst low temperatures may slow them down, it would need to be below minus 16 degrees Celsius to kill them. The silken homes are carefully positioned to take advantage of the sun’s heat and this warmth is absorbed into the nest thereby aiding the resting caterpillars to digest their previous night’s meal. Also the fact that there can be up to 300 caterpillars in a nest helps to keep the nest warmer by as much as a degree or two than the outside temperature.The pine processionary caterpillar (Thaumetopoea pityocampa) is known as ‘procesionaria del pino’ in Spanish and during late winter/early spring they will be coming out of the trees and forming conspicuous snakelike lines as they traverse the ground searching for soft soil to burrow into. They will not be far from a pine tree, but that does not mean that you will only see them in large pine woods, they are just as likely to be found in urbanisations and road side plantings wherever pine trees are present.
There are several stages within their lifecycle but they are only dangerous to people and pets during the caterpillar phase. In the adult phase they are a simple and unremarkable, short lived moth which emerges in the summer and flies at night. The male moth is attracted to the female moth by pheromones that she emits. They will mate and a single female can then lay up to 300 tiny eggs which she attaches in a mass to a pine needle. Around one month later these eggs hatch into minute caterpillars. These larvae have 5 growth stages that are called “instars”.  They grow quickly in body size, moult their skin and that denotes the start of the next instar.

These social caterpillars living in family communities eat pine needles by night and sleep in little temporary silk nests by day. At this point they are nomadic and the nests are not really visible. However at the third instar (moult) the siblings build a permanent white silky nest on the tip of a pine branch. These appear during the winter as white cotton or ‘candyfloss’ like structures and a single pine tree may have many. If there are half a dozen or more in the top of a tree they can easily strip the leaves with their nightly foraging, possibly clearing all greenery off some branches and in many cases damaging the tree badly.  By feeding under the cover of darkness they avoid attack by birds and predatory wasps. At dusk the caterpillars leave their communal nest in search of food, there is no single entrance hole, they simply push through the silk layers and once onto a branch they will leave a scent trail to help themselves find their way back before the morning light arrives.

This period of night time eating occurs during the winter months and whilst low temperatures may slow them down, it would need to be below minus 16 degrees Celsius to kill them. The silken homes are carefully positioned to take advantage of the sun’s heat and this warmth is absorbed into the nest thereby aiding the resting caterpillars to digest their previous night’s meal. Also the fact that there can be up to 300 caterpillars in a nest helps to keep the nest warmer by as much as a degree or two than the outside temperature.The pine processionary caterpillar (Thaumetopoea pityocampa) is known as ‘procesionaria del pino’ in Spanish and during late winter/early spring they will be coming out of the trees and forming conspicuous snakelike lines as they traverse the ground searching for soft soil to burrow into. They will not be far from a pine tree, but that does not mean that you will only see them in large pine woods, they are just as likely to be found in urbanisations and road side plantings wherever pine trees are present.
There are several stages within their lifecycle but they are only dangerous to people and pets during the caterpillar phase. In the adult phase they are a simple and unremarkable, short lived moth which emerges in the summer and flies at night. The male moth is attracted to the female moth by pheromones that she emits. They will mate and a single female can then lay up to 300 tiny eggs which she attaches in a mass to a pine needle. Around one month later these eggs hatch into minute caterpillars. These larvae have 5 growth stages that are called “instars”.  They grow quickly in body size, moult their skin and that denotes the start of the next instar.

These social caterpillars living in family communities eat pine needles by night and sleep in little temporary silk nests by day. At this point they are nomadic and the nests are not really visible. However at the third instar (moult) the siblings build a permanent white silky nest on the tip of a pine branch. These appear during the winter as white cotton or ‘candyfloss’ like structures and a single pine tree may have many. If there are half a dozen or more in the top of a tree they can easily strip the leaves with their nightly foraging, possibly clearing all greenery off some branches and in many cases damaging the tree badly.  By feeding under the cover of darkness they avoid attack by birds and predatory wasps. At dusk the caterpillars leave their communal nest in search of food, there is no single entrance hole, they simply push through the silk layers and once onto a branch they will leave a scent trail to help themselves find their way back before the morning light arrives.

This period of night time eating occurs during the winter months and whilst low temperatures may slow them down, it would need to be below minus 16 degrees Celsius to kill them. The silken homes are carefully positioned to take advantage of the sun’s heat and this warmth is absorbed into the nest thereby aiding the resting caterpillars to digest their previous night’s meal. Also the fact that there can be up to 300 caterpillars in a nest helps to keep the nest warmer by as much as a degree or two than the outside temperature.The pine processionary caterpillar (Thaumetopoea pityocampa) is known as ‘procesionaria del pino’ in Spanish and during late winter/early spring they will be coming out of the trees and forming conspicuous snakelike lines as they traverse the ground searching for soft soil to burrow into. They will not be far from a pine tree, but that does not mean that you will only see them in large pine woods, they are just as likely to be found in urbanisations and road side plantings wherever pine trees are present.
There are several stages within their lifecycle but they are only dangerous to people and pets during the caterpillar phase. In the adult phase they are a simple and unremarkable, short lived moth which emerges in the summer and flies at night. The male moth is attracted to the female moth by pheromones that she emits. They will mate and a single female can then lay up to 300 tiny eggs which she attaches in a mass to a pine needle. Around one month later these eggs hatch into minute caterpillars. These larvae have 5 growth stages that are called “instars”.  They grow quickly in body size, moult their skin and that denotes the start of the next instar.

These social caterpillars living in family communities eat pine needles by night and sleep in little temporary silk nests by day. At this point they are nomadic and the nests are not really visible. However at the third instar (moult) the siblings build a permanent white silky nest on the tip of a pine branch. These appear during the winter as white cotton or ‘candyfloss’ like structures and a single pine tree may have many. If there are half a dozen or more in the top of a tree they can easily strip the leaves with their nightly foraging, possibly clearing all greenery off some branches and in many cases damaging the tree badly.  By feeding under the cover of darkness they avoid attack by birds and predatory wasps. At dusk the caterpillars leave their communal nest in search of food, there is no single entrance hole, they simply push through the silk layers and once onto a branch they will leave a scent trail to help themselves find their way back before the morning light arrives.

This period of night time eating occurs during the winter months and whilst low temperatures may slow them down, it would need to be below minus 16 degrees Celsius to kill them. The silken homes are carefully positioned to take advantage of the sun’s heat and this warmth is absorbed into the nest thereby aiding the resting caterpillars to digest their previous night’s meal. Also the fact that there can be up to 300 caterpillars in a nest helps to keep the nest warmer by as much as a degree or two than the outside temperature.The pine processionary caterpillar (Thaumetopoea pityocampa) is known as ‘procesionaria del pino’ in Spanish and during late winter/early spring they will be coming out of the trees and forming conspicuous snakelike lines as they traverse the ground searching for soft soil to burrow into. They will not be far from a pine tree, but that does not mean that you will only see them in large pine woods, they are just as likely to be found in urbanisations and road side plantings wherever pine trees are present.
There are several stages within their lifecycle but they are only dangerous to people and pets during the caterpillar phase. In the adult phase they are a simple and unremarkable, short lived moth which emerges in the summer and flies at night. The male moth is attracted to the female moth by pheromones that she emits. They will mate and a single female can then lay up to 300 tiny eggs which she attaches in a mass to a pine needle. Around one month later these eggs hatch into minute caterpillars. These larvae have 5 growth stages that are called “instars”.  They grow quickly in body size, moult their skin and that denotes the start of the next instar.

These social caterpillars living in family communities eat pine needles by night and sleep in little temporary silk nests by day. At this point they are nomadic and the nests are not really visible. However at the third instar (moult) the siblings build a permanent white silky nest on the tip of a pine branch. These appear during the winter as white cotton or ‘candyfloss’ like structures and a single pine tree may have many. If there are half a dozen or more in the top of a tree they can easily strip the leaves with their nightly foraging, possibly clearing all greenery off some branches and in many cases damaging the tree badly.  By feeding under the cover of darkness they avoid attack by birds and predatory wasps. At dusk the caterpillars leave their communal nest in search of food, there is no single entrance hole, they simply push through the silk layers and once onto a branch they will leave a scent trail to help themselves find their way back before the morning light arrives.

This period of night time eating occurs during the winter months and whilst low temperatures may slow them down, it would need to be below minus 16 degrees Celsius to kill them. The silken homes are carefully positioned to take advantage of the sun’s heat and this warmth is absorbed into the nest thereby aiding the resting caterpillars to digest their previous night’s meal. Also the fact that there can be up to 300 caterpillars in a nest helps to keep the nest warmer by as much as a degree or two than the outside temperature.The pine processionary caterpillar (Thaumetopoea pityocampa) is known as ‘procesionaria del pino’ in Spanish and during late winter/early spring they will be coming out of the trees and forming conspicuous snakelike lines as they traverse the ground searching for soft soil to burrow into. They will not be far from a pine tree, but that does not mean that you will only see them in large pine woods, they are just as likely to be found in urbanisations and road side plantings wherever pine trees are present.
There are several stages within their lifecycle but they are only dangerous to people and pets during the caterpillar phase. In the adult phase they are a simple and unremarkable, short lived moth which emerges in the summer and flies at night. The male moth is attracted to the female moth by pheromones that she emits. They will mate and a single female can then lay up to 300 tiny eggs which she attaches in a mass to a pine needle. Around one month later these eggs hatch into minute caterpillars. These larvae have 5 growth stages that are called “instars”.  They grow quickly in body size, moult their skin and that denotes the start of the next instar.

These social caterpillars living in family communities eat pine needles by night and sleep in little temporary silk nests by day. At this point they are nomadic and the nests are not really visible. However at the third instar (moult) the siblings build a permanent white silky nest on the tip of a pine branch. These appear during the winter as white cotton or ‘candyfloss’ like structures and a single pine tree may have many. If there are half a dozen or more in the top of a tree they can easily strip the leaves with their nightly foraging, possibly clearing all greenery off some branches and in many cases damaging the tree badly.  By feeding under the cover of darkness they avoid attack by birds and predatory wasps. At dusk the caterpillars leave their communal nest in search of food, there is no single entrance hole, they simply push through the silk layers and once onto a branch they will leave a scent trail to help themselves find their way back before the morning light arrives.

This period of night time eating occurs during the winter months and whilst low temperatures may slow them down, it would need to be below minus 16 degrees Celsius to kill them. The silken homes are carefully positioned to take advantage of the sun’s heat and this warmth is absorbed into the nest thereby aiding the resting caterpillars to digest their previous night’s meal. Also the fact that there can be up to 300 caterpillars in a nest helps to keep the nest warmer by as much as a degree or two than the outside temperature.

(And from Biology Online) The winter pine processionary moth, Thaumetopoea pityocampa offers a possibility to test for the effects of global warming on an insect population over a wide area of the Mediterranean basin and southern parts of Europe, where it is the most important pest of pine forests (Pinus spp.). Its geographic range lies within precise limits of elevation and latitude, primarily as a function of the average winter temperatures. Because the larvae are oligophagous, potentially feeding on all Pinus spp., but also on Cedrus spp. and the introduced Pseudotsuga menziesii, host plant distribution does not restrict the present range of the insect; many usual or potential host species grow in areas where the insect is absent. Consequently, if the climatic conditions become favourable in higher latitudes or at higher elevations, the insect may expand its range to these areas, often coupled with host switching. This relative importance of temperature over biotic factors in defining the geographic distribution makes the moth a particularly suitable model to study the range shift in relation to global warming.

An important forest pest in many areas, the moth has shown in the last decades a substantial expansion of the outbreak area both northward and upward, aggravated by extreme climatic events such as the summer of 2003. This has resulted in high attack rates in areas previously largely unaffected by the insect. The case deserves special interest for the implications it may have on the management of European forests and plantations, as well as on ornamental trees.

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