9. THE CLASS CRUSTACEA
335
6. Other Crabs Associated with Pelecypods
Crabs of the family Xanthidae, commonly known as mud crabs,
are known to include certain species which are predators of the
American oyster, Crassostrea virginica, and other pelecypods. For
example, according to McDermott (1960), both Chestnut (unpublished)
and Smith and Richards (unpublished) have shown that mud crabs,
probably Panopeus herbsti, prey on Crassostrea virginica in New Jersey
waters. It has been reported that a single crab will destroy thirty
oysters in a month under laboratory conditions. McDermott and
Flower (1952) have reported that Panopeus herbsti is an active predator
of 1- or 2-year-old oysters. Similarly, Menzel and Hopkins (1956) have
reported that another xanthid crab, Menippe mercenaria, preys on
oysters, and Landers (1954) has reported that in Rhode Island another
species, Neopanope texana preys on young Mercenaria mercenaria.
McDermott (1960) has reported that Panopeus herbsti, Neopanope
texana sayi and Eurypanopeus depressus will all prey on Crassostrea
virginica in nature and that under laboratory conditions Panopeus
herbsti will destroy 1- to 2-year-old oysters at the rate of 0.15 oyster per
crab per day. He has also demonstrated a selectivity on the part of
this crab for the smaller, thin-shelled specimens.
The predatory xanthid crabs are being briefly mentioned here to
emphasize that these are not parasites sensu strictu but are of importance
to the shellfisheries industry. For a listing of the literature pertaining
to the ecology of xanthid crabs, the paper by Ryan (1956) should be
consulted.
335
6. Other Crabs Associated with Pelecypods
Crabs of the family Xanthidae, commonly known as mud crabs,
are known to include certain species which are predators of the
American oyster, Crassostrea virginica, and other pelecypods. For
example, according to McDermott (1960), both Chestnut (unpublished)
and Smith and Richards (unpublished) have shown that mud crabs,
probably Panopeus herbsti, prey on Crassostrea virginica in New Jersey
waters. It has been reported that a single crab will destroy thirty
oysters in a month under laboratory conditions. McDermott and
Flower (1952) have reported that Panopeus herbsti is an active predator
of 1- or 2-year-old oysters. Similarly, Menzel and Hopkins (1956) have
reported that another xanthid crab, Menippe mercenaria, preys on
oysters, and Landers (1954) has reported that in Rhode Island another
species, Neopanope texana preys on young Mercenaria mercenaria.
McDermott (1960) has reported that Panopeus herbsti, Neopanope
texana sayi and Eurypanopeus depressus will all prey on Crassostrea
virginica in nature and that under laboratory conditions Panopeus
herbsti will destroy 1- to 2-year-old oysters at the rate of 0.15 oyster per
crab per day. He has also demonstrated a selectivity on the part of
this crab for the smaller, thin-shelled specimens.
The predatory xanthid crabs are being briefly mentioned here to
emphasize that these are not parasites sensu strictu but are of importance
to the shellfisheries industry. For a listing of the literature pertaining
to the ecology of xanthid crabs, the paper by Ryan (1956) should be
consulted.