Winter miracles

Dry seasonal pools revive when the rain returns.

Songbird (photo credit: TALI NOY MEIR)
Songbird
(photo credit: TALI NOY MEIR)
If I didn’t know better, I’d think I was standing before a large pond. The reed-edged water rippled in the mild winter sunshine. Red dragonflies with transparent wings flitted around. A frog announced in a startling baritone that he was boss around here. In the middle of the pool, a couple of male mallard ducks paddled, gorgeous in blue and brown feathers, their discreetly clad brown wives behind. A few more ducks sailed over to see what the big deal was. Then all went head down into the water, irresistibly reminding me of the Rat’s poem in The Wind In The Willows: “All along the backwater, Through the rushes tall, Ducks are a-dabbling, Up tails all!” Sacred ibises swept the sky. They, the ducks and other birds are wild visitors to the Herzliya winter water pools, taking their leisure between travels.
Once, more than 1,500 winter pools graced Israel’s landscape. In summer, they’re dry tracts in low-lying country, looking like nothing special until the rains come. Then the depressions in the land become drainage basins, as gravity carries river overflow and surface runoff to them. The water gathers and forms large pools.
The pool bottoms are of hard clay, which prevents the water from draining away. Rainfall helps fill them in, and a whole aquatic ecosystem spontaneously appears.
Reeds and other water-loving plants sprout and flower.
Migrating birds make the pools a way station on their way south. Hopping frogs and toads croak their territorial challenges. Newts, tadpoles, water insects and tiny crabs populate the water. In the old days, people living nearby used the pools for irrigation and to water flocks.
Come summer, most of those pools dry up. The birds take off again. The frogs and dragonflies die. But life sleeps in eggs laid by the previous generation of amphibians and insects. In the dry dirt, embryonic creatures inside hard shells wait for the next winter’s rains.
Plant seeds lie dormant, too. As soon as fresh waters roll into the area and jostle the eggs and seeds to life, a new food chain comes into being, making the winter pools inviting to birds and small mammals again. The rich, albeit fragile habitat that is Israel’s winter pools returns – a miracle, in a way.
Today, only 5 to 10 percent of Israel’s winter pools survive. Expanding towns have put roads and buildings over some, or water sources have been diverted by construction.
Other pools have been filled in to make farm fields. As a result, several native species are in danger of extinction. Newts and the spadefoot toad are prime examples, but some native plants are also in danger of vanishing with the ponds. Metro took a walk around the Herzliya City Park’s winter pools with ecologist Dr. Eldad Elron, adviser to the park’s directors on everything connected to the pools.
“The pools here are very old,” explained Elron. “The park itself was part of a swamp recorded in a map made by the British in 1880. On that map you can see seasonal pools, swamps and springs. This seasonal pool is highlighted as a large, ancient one. Parts of it were so big that they remained even by the end of the summer. Today it’s not as big as the historical pool, but still fairly large.
“The difference between a swamp and a seasonal pool is that a swamp has water all year round. The level rises or drops, but there’s always water. A seasonal pool – and this is unique – has a water phase in the winter, and a dry one in the summer. This is very important, because without the dry season you don’t get the variety of life in winter. If the water stays, it attracts fish that prey on other life forms.”
I learned that the pools sustain snails, amphibians, worms, leeches and water insects. There are two bird observation shacks on the grounds around the pools. To help identify the birds, there are pictures of them, with their names and descriptions, inside the observatories. You may spot Egyptian geese, cattle egrets, great white herons, lapwings, the greater spotted eagle and many others.
“The Herzliya Municipality made a unique decision not to dry all the area and make it into a park, but to keep part of it natural,” said Elron. “We don’t know everything about how winter pools affect the environmental balance, but we do know that each element affects and interacts with each other. The plants photosynthesize; creatures eat the plants and are eaten in turn. Plants also attract insects such as bees, important pollinators for many crops we depend on.”
Winter ponds and their plants act as filters that clean the water, which eventually penetrates aquifers. Monitoring the water quality of the ponds reveals much about the health of the local environment. But do the pools contribute to mosquitoes? “No,” says Elron emphatically. “They actually help control mosquitoes because the birds, frogs and other insects eat them and their eggs. People used to blame the winter pools for mosquitoes. People sprayed pesticides and introduced gambusia fish into the water, hoping to control the mosquitoes. The gambusias ignore the mosquitoes and feed on embryonic amphibians to the point where the amphibians are in danger of disappearing.
When people spray pesticides or introduce strange fish into the pools, they interfere with the balance of the whole food chain there.”
The Society for Protection of Nature in Israel works constantly to rehabilitate seasonal pools, running campaigns to uproot invasive plant species and cleaning water sources where trash has accumulated. Workers bring life back to rehabilitated pools by the simple method of taking dirt from existing healthy pools and placing it in the pool under treatment. The eggs and seeds naturally present in the dirt hatch and sprout again when the rains come, starting a new life cycle in the pool. This method is also used for cross-breeding populations from different pools in order to strengthen them.
Israel’s winter pools provide an opportunity for children and adults to learn the value of our natural sites, and how important it is to preserve them. Most are near towns. The Herzliya pools are actually located inside the city park. They’re an accessible resource for nature studies and research.
In a world where most of the population is moving away from the country and filling cities, many have lost contact with nature. As long as the seasonal pools continue to return, urban dwellers will have quiet, green places in which to contemplate a sunset, jog in fresh air, or just breathe. 
For information and detailed directions to pools around the country, call the KKL-JNF hotline: 1-800-350-550.