Bosses at Bristol Zoo Gardens have launched an investigation after the incident came to light.
It has been alleged that a senior animal keeper punched the South American fur seal when handlers tried to weigh it.
The zoo’s head vet has examined all the seals at the popular tourist attraction and they remain on public show in their enclosure.
A Bristol Zoo Gardens spokeswoman said: “A senior animal keeper has been suspended pending further investigation of an alleged animal welfare incident that has recently come to light.
“As this is an ongoing investigation, Bristol Zoo is currently unable to discuss the details of the incident.
“However, the zoo has acted rapidly and comprehensively by instigating an immediate, formal and extensive investigation in line with its internal policies and legal welfare requirements.
“Michelle Barrows, head of veterinary services, has examined the seal family and all individuals are behaving normally, engaging happily and playfully with keepers and guests in their enclosure.
“The animal has been, and continues to be, on full public show.
“Bristol Zoo would like to make it very clear that it has a zero tolerance towards such behaviour.”