The researchers bred rotifers in three different environments: one in which the quality of available food was high, one in which it was low and one in which it was mixed.

The stone-curlew reached a low of around 160 breeding pairs in the 1980s, but this year 370 pairs are known to have bred.

Sulfur content low, stable and reliable, effective conservation of sulfur ball and bred in the course of the adverse effects of the alloy, alloy cost savings.