A necropsy will be performed on the carcass of a baby humpback whale that died Monday night off of an East Honolulu beach to determine the exact cause of death. 

The whale, believed to be a few days old, died off of Kawaikui Beach Park near Aina Haina and was removed from the area by city workers at about 10:30 a.m. Tuesday and taken to Hawaii Pacific University for the necropsy.  

David Schofield, manager of the National Oceanic and Atmospheric Administration’s regional marine mammal health and response program, described the calf as a male, approximately 13 feet long and 2,550 pounds. 

The baby whale got stuck in shallow waters off of the beach park Monday and struggled to escape the reef. It was discovered partially tangled in a fishing net in the late afternoon. Officials said the net did not cause the grounding and that the whale was likely already in trouble before it became entangled.

The mammal died at about 9 p.m.