I sounds like what happens with varroa.
The confirmation would be to examine the remaining capped brood cells.
If varroa was responsible for the problem, the mites will be present in
the sealed cells.
good luck
Kerry Clark, Apiculture Specialist
B.C. Ministry of Agriculture
1201 103 Ave
Dawson Creek B.C.
V1G 4J2 CANADA Tel (604) 784-2225 fax (604) 784-2299
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