Alfred Holmes Sgt . Alfred Holmes BEM ( 1 February 1931 – 1 January 1994 ) was a Gibraltarian sergeant of the Gibraltar Regiment ( now the Royal Gibraltar Regiment ) . He was a well remembered " Officer - in - Charge of the Apes " who held this position , caring for the Gibraltar Barbary macaques , for over 38 years . He described the macaques as " Gibraltar ' s greatest treasure " . Early life . Holmes was a second generation Gibraltarian , born in Gibraltar to Gibraltarian parents " Arthur Frederick Holmes " and " Mercedes Carrara " . His father had been previously married and fathered five children from that relationship . Following the death of his wife , he married Mercedes who was later to be Alfred ' s mother . Alfred was to be the only child out of that relationship as his mother died when he was just three years old . His father later remarried one final time , fathering a further five children , giving Alfred a total of ten half sibling s . In 1954 he married Spanish domestic worker " Leonor Corbacho Velasco " , a young lady from in Valverde del Fresno ( Cáceres ) . He had previously met her in La Línea de la Concepción , the Spanish municipality on the other side of the Gibraltar frontier , where she resided at the time . They went on to have two children , " Maria de las Mercedes " in 1955 and " Edward Maximo " in 1962 . Career . In the 1950s , Holmes enlisted in the Gibraltar Regiment where he later ascended to the rank of sergeant . He was appointed " Officer - in - Charge of the Apes " . From 1913 to 1991 the Gibraltar Barbary Macaques have been the responsibity of the British Army , which appointed a non - commissioned officer from the Gibraltar Regiment as " Officer - in - Charge of the Apes " . During his service , Sgt . Holmes fed nursed and guarded the monkeys , generally working to maintain their well - being . He knew all of the macaques by the names he himself had given them . They were mostly named after Governors , brigadiers and high - ranking officers as well as his children . Sgt . Holmes could communicate with the animals by means of eye signals and barely perceptible head movements which he would use to stop them from taking food offered to them by tourists . He would even take young orphaned monkeys to his wife to help rear at home . He would also take sick or injured monkeys to the Royal Naval Hospital where they would receive the exact medical treatment as an enlisted soldier . For his work with the macaques , he was best known locally by the nickname of " " El de los monos " " ( ) . Sgt . Holmes ' time in the job made him an authority on this group of Barbary Macaque s , with his knowledge being sought by various scientific studies on the monkeys from around the globe . He described the macaques as " Gibraltar ' s greatest treasure " . Death . In the early 1990s , Holmes was diagnosed with esophageal cancer , later traveling to London to undergo major abdominal surgery . The cancer eventually resulted in his death on 1 January 1994 at Old St . Bernard ' s Hospital in Gibraltar . His body now rests in a family grave together with his father , grandfather and various half siblings at North Front Cemetery , Gibraltar .