N90 CTLR EXPERIENCED OPERROR AT 7000 FT BY ISSUING LATE TURN AND ALLOWING ACFT TO ENTER ADJACENT CTLR'S AIRSPACE; RESULTING IN A CONFLICT. STAFFING ISSUES ARE LISTED AS CONTRIBUTORY.

Narrative

WORKING A RADAR POS THAT FEEDS THE FINAL APCH CTLR AT LGA; WE WERE IN A HOLD DUE TO VOLUME. I HAD BEEN VECTORING FOR HOLDING 3 ACFT; ALL JETS AT 3 DIFFERENT ALTS. ALTHOUGH THERE IS A PUBLISHED HOLD ON THE STAR; MOST PLTS ARE UNFAMILIAR WITH IT; AND BECAUSE IT HAS ONLY 1 MIN LEGS AND NO ROOM TO APPROVE LONGER ONES; PLTS PREFER THE VECTORS. THE RADAR POS NEXT TO ME (COMBINED ARR AND DEP FOR HPN) WAS EXTREMELY BUSY. THE STAFFING LEVEL IN THE FACILITY IS SUCH THAT WE DID NOT HAVE ANOTHER CTLR TO OPEN UP THE DEP POS; SO EVEN THOUGH I WAS HOLDING; I WAS TOLD TO TAKE ON THE DEP POS. NOT GETTING ANY ASSISTANCE FROM THE SUPVR; I WAS DISTR BY THE TASK OF RECONFIGURING THE RADAR POS AND COORDINATING THE FREQS FROM ALL OF THE ADJOINING SECTORS AND TWRS. THIS CAUSED ME TO TURN AN E135 TOO LATE TO KEEP THEM IN MY AIRSPACE AND ALLOWED THEM TO COME INTO CONFLICT WITH A CESSNA AT 7000 FT. I NOTICED THE CONFLICT AND ISSUED THE TFC ALERT AND A CLB FOR AVOIDANCE; BUT A LOSS OF SEPARATION OCCURRED. STAFFING LEVELS IS A DIRECT CAUSE OF THIS INCIDENT.