Cyprinid hybrids
The appearance of hybrids between fairly closely-related members of the family Cyprinidae (the
carps and minnows j is a common occurrence in unnatural waters. The Forest ponds are no exception
and hybrids between Bream and Roach have been recorded, while it is fairly certain that Crucian Carp
and Carp have hybridized where both are present in the water. The incidence of hybridization is
increased when species are introduced to a water and also in small waters (such as the Forest ponds),
when suitable spawning conditions are sparse and when ethological barriers break down due to
proximity or other causes. Many such hybrids are sexually sterile or have only low fertility; for this
reason the occurrence of back-crosses with parental species does not seem to occur in the wild
(although they have been produced in the laboratory).
Stone Loach Nemacheilus barbatulus L.
Specimens were found in the pond on Theydon Green and at Fairmead Bottom Pond in 1985 and
1989. Both are totally unsuitable habitats for this species, and these fish must have been recently
introduced. Mr. Peter Adams has reported this species from the Ching Brook, a more plausible natural
habitat for this fish.
Three-spined Stickleback Gasterosteus aculeatus L.
Very widely distributed in all ponds and their tributary streams. Recorded from Bell Common
Pond (Wheeler, 1990), pond at Theydon Green, Goldings Hill Pond (outer), Blackweir Pond, Earls
Path Pond and the Eagle Pond (Harris, Ms). The populations in these ponds fluctuate enormously
over the years. This may be due partly to physiological changes in response to stress (Wheeler, 1990)
but the effects of heavy parasite loads in some years could also explain their occasional scarcity.
Sticklebacks have also been caught in the River Ching near Highams Park, Whitehall Plain and
Connaught Water, and are found in the Cuckoo Brook near the Cuckoo Pits. They also occur in the
Loughton Brook upstream and downstream of Baldwins Pond. These riverine populations are
ephemeral and become isolated into small pools in the stream bed during drought.
Perch Perca fluviatilis L.
Occurs in all the larger ponds and many of the small ones. Its occurrence in the following ponds
has been recently confirmed - the Lake (Lower Forest), Baldwins Pond, Wake Valley Pond, Blackweir
Pond, Earls Path Pond. Connaught Water, Warren Pond, Eagle Pond (Harris Ms) and the Wanstead
Park Ponds.
Pumpkinseed Lepomis gibbosus L.
A North American fish which is sold for the aquarium and pond. Reports of its capture have been
noted from the Hollow Pond and the Ornamental Water in Wanstead Park. These may have been
isolated specimens, but they may also be evidence of established populations such as have been found
elsewhere in South-East England (e.g. Hampstead Heath and lakes at Crawley, Surrey).
Bullhead Cottus gobio L.
Reports of the occurrence of this fish have been received from the lower reaches of the Loughton
Brook (P. A. Moxey) and the River Ching, below Highams Park Lake (G. Rawlings). This is a riverine
fish and both localities are in accordance with its biology.
Discussion
Virtually all of the fishes recorded from Epping Forest have been introduced by man, the only
exceptions being the Stone Loach, Three-spined Stickleback and the Bullhead, which are possibly
naturally occurring in the streams in which they have been reported, and the Eel. However, of these,
two have been introduced to ponds, the Stickleback on a large scale and the Stone Loach occasionally.
Most of the introductions involve fishes which are of interest to anglers. In 1714 the Court of
Attachments granted a licence to Jeremy Wakeling of Walthamstow 'to digg a pond upon ye Wast
ground within ye said fforest and to stock or store ye same with Fish for his own use' (CAI p. 15).
More recently various angling clubs have introduced fish (usually with the permission of the
Conservators) over the years, but there has also been a steady, probably small scale, unofficial release
of fishes to ponds. In recent years this has been illegal under fisheries legislation and particularly so
in the areas of the Forest designated as an SSSI.
Some of the species introduced to the ponds have failed to thrive (e.g. the Bream in Connaught
Water), but many have established viable populations. Not surprisingly these are all lentic species
such as the Carp, Crucian Carp, Tench, Roach, Perch and Pike. The shallow, eutrophic conditions
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