Newt life cycles closely resemble those of frogs and toads, but their metamorphosis is less dramatic because they retain their swimming tail as adults. They breed in the spring, and males grow breeding displays of crests. Although adult newts are less weighty than frogs, their larvae are predators on frog tadpoles. Quite often, as newt populations grow in garden ponds, the garden frogs seem to disappear. Smooth newts in the wild live for about 6 years, maturing at 2-3. Great crested newts can live as long as 16 years in the wild, and much longer in captivity.
Breeding success can vary greatly from year to year, especially in great crested newts which have been studied more thoroughly. Whole annual cohorts can be eliminated by ponds drying up, or by introduction of fish, while in some years survival rates can be exceptional.
On land, newts feed on slugs, snails, worms, spiders and insects. In the pond they eat small crustaceans and insects, and pond snails which they wrestle from their shells. In turn, newts are eaten by foxes, badgers, hedgehogs and several predatory bird species.
Helpers in the garden
All amphibians perform a useful garden role in eating the slugs, snails and other invertebrates that are the bane of many wildlife gardeners who prefer not to use chemical pest control. If you’re planning a wildlife pond and want to encourage amphibians
• site your pond in a sunny spot away from overhanging trees and shrubs
• include gently-sloping sides to allow young amphibians to enter and leave the pond easily
• try to include a section at least 60cm deep in which frogs can hibernate without being frozen
• create about 30% cover of a mixture of aquatic plants, and surround the pond with marginal
• avoid adding any fish.
The terrestrial habitat provided by the garden is also important for amphibians – they will be attracted by insects in flowery borders as well as patrolling vegetable plots for pests. A rough area with logs or boards in a quiet corner will provide hiding places where they can spend the day. Bog gardens and shaded densely vegetated areas help in dry periods, and rockeries make ideal overwintering habitat. When newly metamorphosed frogs leave the pond in late summer, be very careful when mowing the lawn not to destroy them, and if you can, give them time to disperse to flower beds and rough ground.
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