Fifty years ago the River Thames was considered biologically dead, but
water
quality has improved vastly since then. A recent count showed
that there are now 120 species of fish in the river, including red
mullet, anchovies, bass and the occasional salmon. The Wildlife and
Countryside Act of 1981 contributed to the protection of these
creatures by making it illegal to kill or capture them.
Trout were released into the River Wandle, a tributary of the Thames, a few years back. Horatio Nelson would be pleased. It was one of his favourite fishing spots 200 years ago.
The past couple of years have seen a few isolated records of seahorses in the Thames estuary but recently the Zoological Society of London announced the discovery of a breeding population of short-snouted seahorses (Hippocampus hippocampus), which are normally found in shallow muddy waters, beds of seagrass and estuaries in the Mediterranean and Atlantic. The discovery was kept secret for 18 months until the Act could be amended to protect them as well.
Seahorses are used in traditional Chinese medicine, mainly as an aphrodisiac. Large, pale, smooth types are preferred but as most are sold in prepackaged form nowadays the exact species is often impossible to recognise. It is thought that well over 25 million seahorses are caught worldwide for this purpose each year, many taken illegally.
