VAN REISEN J (2022) The influence of water extraction on duck populations in the dunes. LIMOSA 95 (3): 134-144.
At the end of the 18th century, water was extracted from the
dunes to provide clean drinking water for cities near the
coast. As a result, dunes dried up, at the expense of flora
and fauna. To avoid negative effects of water extraction on
the dunes, drinking water companies decided to infiltrate
river or reservoir water into the dunes. Due to the filtering
effect of the sand, suitable drinking water was obtained after
several months. In this way drinking water could be obtained
in a more sustainable way, meeting the needs for clean
drinking water of a growing human population. Infiltration
coincided with a strong increase in breeding ducks as a lot
of new freshwater habitat was created. In addition, due to
the nutrient-rich inlet water, vegetation along the banks of
the infiltration ponds developed, which provided shelter
and nesting opportunities. However, due to the high
phosphate content of the inlet water, banks ultimately got
overgrown with bushes, and the characteristic nutrient-limited dune vegetations disappeared. This forced drinking
water companies to purify the inlet water. As a result, the
authentic dune vegetation recovered, but the numbers of
ducks decreased. The exception is the Red-crested Pochard
Netta rufina, which profited from the improvement of the
water quality
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