Alimentazione della Beccaccia, vermi, Piogge e Neve acide

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ALIMENTAZIONE della Beccaccia , VERMI , Piogge e Neve ACIDE -
Food: Earthworms, high in fat and protein, make up

about 60 percent of a woodcock’s diet. An additional

30 percent is insects (ants, flies, beetles,

crickets, caterpillars, grasshoppers and various

larvae), crustaceans, millipedes, centipedes

and spiders. About 10 percent

is plant food, mostly seeds from

bristlegrass, panicgrass, sedge, ragweed,

knotweed and blackberry.

Timberdoodles do most of their

feeding in the early evening

and just before dawn. Digestion

is rapid; an adult may

eat its weight in worms

each day.
Earthworms provide about 60 percent of the bird's diet. The worms are high in fat and protein; they provide the necessary nutrients to help keep woodcock healthy and strong. An additional 30 percent of a woodcock diet consists of insects such as ants, flies, beetles, crickets, caterpillars, grasshoppers and various larvae. They've also been known to eat crustaceans, millipedes, centipedes and spiders.


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"The Earthworm" redirects here. For other uses, see Earthworm (disambiguation).


Lumbricus terrestris, the Common Earthworm

Scientific classification












Almidae (disputed)

Earthworm is the common name for the largest members of Oligochaeta (which is either a class or subclass depending on the author) in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female. Theoretical cladistic studies have placed them instead in the suborder Lumbricina of the order Haplotaxida, but this may again soon change. Folk names for the earthworm include "dew-worm", "Rainworm", "night crawler" and "angleworm" (due to its use as fishing bait).

Earthworms are also called megadriles (or big worms), as opposed to the microdriles (or small worms) in the families Tubificidae, Lumbriculidae, and Enchytraeidae, among others. The megadriles are characterized by having a distinct clitellum (which is much more obvious than the single-layered one of the microdriles) and a vascular system with true capillaries.



  • 1 Anatomy

  • 2 Reproduction

  • 3 Digestion

  • 4 Regeneration

  • 5 Behavior

    • 5.1 Rainstorms and "Stranding" Behavior

  • 6 Locomotion and importance to soil

  • 7 Benefits

  • 8 Earthworms as invasive species

    • 8.1 Australia

    • 8.2 North America

    • 8.3 United Kingdom

  • 9 Special habitats

  • 10 Ecology

  • 11 Economic impact

  • 12 Taxonomy and distribution

  • 13 See also

  • 14 References

  • 15 Further reading

  • 16 External links


This page provides a summary of the main features of earthworms. In particular the classification refers to one of the common earthworms found in New Zealand. I plan to add diagrams and a glossary, check back later.




- segmented worms









The earthworm feeds on organic matter in the soil and plant matter which it drags down into its burrow

It uses it pharynx to suck food or soil into its mouth

The oesophageal glands add chalk to neutralise any acidity in the soil

The crop temporarily stores the food

The gizzard has a horny lining which helps grind up the food into smaller particles

Food is absorbed in the intestine

Undigested food passes out the anus and is deposited as 'worm casts'


Respiration and gas exchange:

  1. The earthworm 'breaths' through its moist skin

  2. Oxygen from the air dissolves in the moisture on the worms skin and then travels into the skin blood capillaries.

  3. The haemoglobin in the blood carries the oxygen around the worms body

  4. CO2 is lost from the body by the opposite process - though CO2 is not carried by the haemoglobin.


Blood system:

  1. Earthworms have a closed circulatory system

  2. Their blood contains red haemoglobin (in solution) to transport oxygen and white blood cells to fight infection

  3. The blood is pumped around the body by 5 pseudohearts (they are like enlarged blood vessels)

  4. The pseudohearts are located around the oesophagus


Nervous system:

  1. Earthworms have no eyes, ears or nose

  2. They can sense light and dark by small light sensitive cells found mainly on the uppers skin surface at the ends of their body

  3. They sense vibrations and chemicals by the means of tiny touch or chemical sensitive cells

  4. Each segment contains a ganglion - a swollen region of nerves which receives messages from that segment.

  5. There is a cerebral ganglion (primitive brain) in segment 3 above the buccal cavity.

  6. The worm will move away from light, vibrations and dangerous chemicals


Support and movement:

  1. Earthworms have a hydrostatic (= fluid) skeleton

  2. They move by squeezing the circular muscles of each segment to make their body extend forward, then they grip the surface with their bristles and contract their longitudinal muscles so their body is pulled up to their anterior (front) end

  3. The above process can occur at several places along the body at the same time



  1. CO2 is excreted through the moist skin

  2. Nitrogen containing waste (from protein breakdown) is removed by nephridia. These are long coiled tubes which remove nitrogen wastes from blood capillaries and excrete it through tiny pores on the skin surface

  3. There are 2 nephridia in each segment



  1. Earthworms are hermaphrodites but they don't fertilise themselves

  2. The worms lie side by side facing opposites directions. They secrete a mucus from their clitellums (= saddles), this hold the worms together. Sperm are released from segment 15 and they travel to the clitellum and into the spermathecae (=sperm storage sacs) on segment 9 and 10 of the other worm

  3. Later the worm secretes a cocoon from its clitellum as it wiggles backwards out of the cocoon the worm releases 8-16 eggs and sperm from the spermathecae .

  4. Usually only one worm hatches from the cocoon


Habitat, niche and environment:

  1. The worms habitat is moist, humus rich soil. In dry weather it burrows deeper into the soil to avoid drying out

  2. The worms niche is a herbivore and macro-decomposer. It is important as a source of food for birds. It also helps aerate the soil and helps increase soil fertility by manuring it with leaf litter

  3. The worms environment is humid, moist and cool

Why Do Earthworms Come Out When it Rains?

By Katelyn Kelley, eHow Contributor

Earthworms tend to surface in large numbers during heavy rains for several reasons, not simply because the oxygen levels in the soil changes. Earthworms need to remain moist to survive and consider rain a good thing.

Earthworm Lungs

  1. Earthworms do not have lungs like humans. Instead, the surface of their skin, known as a cuticle, absorbs oxygen through a process called diffusion.

More Oxygen in Air

  1. The earthworm's cuticle must remain moist to absorb oxygen. When they are in soil, they receive oxygen from air trapped underground. Rain-soaked dirt, however, fills that air space with water, and although earthworms can absorb oxygen from the water, air contains more oxygen, so they will surface for more efficient breathing.

Favorable Moist Conditions

  1. Earthworms must remain moist to breathe and need moisture to move around. After a rain, the conditions above the ground are extremely favorable to them, so they surface to move around without fear of drying out.

Rain Mimics Evening Conditions

  1. Worms come out at night when the air is moist and there is no hot sun to dry their skin. When it rains during the day, the conditions above ground resemble the cool, damp conditions at night, so worms will surface without waiting for nightfall.

Mating Habits

  1. Earthworms have a higher chance of bumping into another worm when they are on the surface after a heavy rain and can travel greater distances. Some species of earthworms seem to prefer mating in moist conditions on the surface because they have more room to maneuver

Read more: Why Do Earthworms Come Out When it Rains? |

What Is Acid Rain?

The term acid rain was coined in 1982, by Robern A. Smith. Acid rain is one of major concerns of biologists and environment researchers. In simpler terms, an acid rain can simply be defined as the event of the rain in which rain water is much more acidic then normal. It is a result of interaction of SOx and NOx with the water vapors and sunlight. This interaction will convert SOx and NOx into strong acidic compounds, like- sulphurous acid, nitrous acid, nitric acid and sulphuric acid.
Now these compounds (called as acid gases or acid particles) along with various organic and in-organic chemicals get deposited in earth’s atmosphere in the form of particulates or aerosols. This deposition is known as Dry Deposition. And then this deposition will be moved to the earth’s surface by snow, rain drops or fog (then this deposition can be said as Wet Deposition). This rain which contains acid particles is known as acid rain.

pH definition of acid rain
In general, clean rain is also observed to be acidic in nature, because it contains different amounts of the natural carbon di oxide of the atmosphere. So, it can be said that a general rain also possesses carbonic acid. Presence of carbonic acid decreases the pH of the rain water. A clean rain’s pH ranges up to 5.6, and this value can be considered as the natural pH of the rain water. So technically, acid rain can be defined as that rain which has pH lesser then 5.6.

Acids of acid rain
Major acid components of acid rain are- H2SO4, HNO3 and HCl. Acid particles and water droplets of the rain get in-corporate with each other by means of impaction, nucleation, diffusiophoresis, Brownian movement, thermophoresis and electrostatic transport. Diffusive mode of incorporation dominates all other mechanisms of incorporation.

Effects of acid rain
Acid rain has serious effects on environment. It produces many irreversible changes. Acidification of lakes and river streams has adverse effects on plants and animals. Acid rain is extremely detrimental for marine life. Green algae and several other types of bacteria play a very important role in maintaining aquatic environment, but acid rain kills all of them by changing their optimum pH environments.
Acid rain has serious effects on soil fertility and vegetation. Acid rain affects the growth rates of the trees and hence it causes lapse of greenery. Because of acid rains, many plant nutritions like potassium, gets leached out from the soil, and it also reduces the population of earth worms. In this way, it can be concluded that acid rain has major effects on soil fertility.

Acid rain is also responsible for many damaging factors like disintegration of the textiles, papers, marbles, buildings and corrosion of the metals etc. Important building structures become weakened and pitted as the soluble sulphates gets leached out by the acid rain. Taj Mahal’s marble blackening is the best suited example to show the effects of acid rain.

Control of acid rain
Simplest solution to decrease the events of acid rain is to neutralize the acids by using lime. But this method is very expensive. Regulated emission of SOx and NOx is the best way to deal with the problem.



Increased freshwater acidity harms some species of migratory birds. Experts believe the dramatic decline of the North American black duck population since the 1950s is because of decreased food supplies in acidified wetlands. Acid rain leaches calcium out of the soil and robs snails of the calcium they need to form shells. Because titmice and other species of songbirds get most of their calcium from the shells of snails, the birds are also perishing. The eggs they lay are defective—thin and fragile. The chicks either do not hatch or have bone malformations and die.

In "Adverse Effects of Acid Rain on the Distribution of the Wood Thrush Hylocichla mustelina in North America" (Proceedings of the National Academy of Sciences, August 12, 2002), Ralph S. Hames et al. discuss the results of their large-scale study, which shows a clear link between acid rain and widespread population declines in the wood thrush, a type of songbird. Hames and his colleagues believe that calcium depletion has had a negative impact on this bird's food source, mainly snails, earthworms, and centipedes. The bird may also be ingesting high levels of metals that are more likely to leach out of overly acidic soils. Declining wood thrush populations are most pronounced in the higher elevations of the Adirondack, Great Smoky, and Appalachian mountains. Hames and his cohorts warn that acid rain may also be contributing to population declines in other songbird species.

Effects of acid rain on bird populations

High elevations, such as the Adirondack, Appalachian and Great Smokey mountains as well as

the Allegheny Plateau, where the amount of acid deposited in precipitation could be highest, show longterm

declines of up to nearly 5 percent annually in wood thrush populations. Although the exact

mechanism leading to the declines is still unknown, it may well be related to the leaching of calcium from

the soil by acid rain. European studies of heavy acid-rain regions similarly have linked declining bird

populations to acid-rain-induced depletion of soil calcium.

Previous studies had shown that calcium-depletion can affect breeding birds in a number of ways.

In particular, shortages of calcium-rich foods, such as snails and snail shells, might be critical at egglaying

time, when calcium demand is highest for female birds, or during the nesting period, when calcium

supplements are often provided to growing young.

However, low levels of soil calcium might also affect a wide range of prey, such as earthworms,

millipedes and centipedes, pillbugs and other insects that adult birds need to nourish themselves and feed

their young. Fallen, decaying leaves and other natural litter on the forest floor could decompose more

slowly under acidic conditions. At the same time, acidic conditions could also increase the amounts of

toxic aluminum and heavy metals (such as lead, cadmium and mercury) that the wood thrush ingests. The

birds may be finding less good-quality food and having to work harder to find it, which could potentially

lead individual thrushes to attempt breeding elsewhere.

Cornell ecologists used data collected in sophisticated statistical analyses to produce a model that

predicted where acid rain's effects might be most severe for a bird whose life and reproductive success

depend on food it finds on the forest floor. The model predicts that, after statistically adjusting for several

other factors (soil, vegetation, topography, thrush abundance), the probability of a wood thrush breeding

is much reduced at a highly acidified site. The negative effects of acid rain might also be heightened by

such factors as high elevation and habitat fragmentation.

Population declines in other songbird species also could be attributable, at least in part, to acid

rain. In some places, there appear to be many fewer birds than there used to be, and these often appear to

be the same places most severely impacted by acid rain.

A locally fairly common migrant but uncommon breeder. Uses open

habitats, such as wet meadows, vegetated wetlands, old fields and
forest clearings, for courtship displays but forages and nests in young
woodland. This species has shown a 50% decline over the last 40
years, predominantly due to loss of early successional stage habitat.
Acid rain and pollution may exacerbate this trend. An important game
species, but effects of hunting on the population are thought to be
Connecticut breeding population may qualify for state listing.

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