Christmas Island Frigatebirds on Jakarta Bay

On 14-15th October 2017 we received an invitation from Seabirds Indonesia (Burung Laut Indonesia) to perform seabirds surveys and monitoring especially to one of the most threatened seabirds in the world that listed on IUCN as critically endangered, the Cristmas Island Frigatebird around Jakarta Bay and marine area of the Kepulauan Seribu National Park, Jakarta.

This big pelagic bird with dominant feather colored black and white is an endemic island of Christmas, a small oceanic island governed by Australia in the eastern Indian Ocean, about 360 km south of Java, Indonesia. Using marine areas in Indonesia especially around Jakarta Bay for forage while breeding with Juvenile which will stay until mature and ready to return for breeding. The highest numbers ever known about Christmas Island Frigatebird are 209 individuals in this location from a total population of about 2400-4800. The numbers were not small considering the threat around Jakarta Bay, among others: Entanglement in fishing gear, Capture and attachment of string to leg, Poisoning / Sedating, and Shooting.

We calculate the age of each individual Christmas Island Frigatebird and look for potential threats in Jakarta Bay and Kepulauan Seribu. In addition to Christmas Island Frigatebird, we also recorded the species of seabirds that use the marine area of Jakarta Bay and Kepulauan Seribu for forage or roosting during the migration season.

In addition, we also conducted a special interview with the head of a group of fishermen on the Harapan island.

Departing from Tanjung Pakis, Tangerang, Banten at around 08.00 am we sailed to sero (Traditional fishing) about 45 minutes. At the sero bamboo stakes that seabirds use for perch, we also counted seabirds passing by and flying around the fishing boats.

We had encountered such as Christmas Island Frigatebird, Great Frigatebird, Lesser Frigatebird, Little Black Cormorant, Greater Crested Tern, Lesser Crested Tern, Common Tern, Black Naped Tern, Brown Noddy, Oriental Darter, Glossy Ibis, Swinhoe’s Storm-petrel.

At 03.30pm we arrived at Harapan island, then headed to the Kepulauan Seribu NP office and met staff and fishermen. 04.30 pm with local staff and fishermen we did afternoon birding around the shoreline of Harapan island. The birds that can be encountered such as: Slender-billed Crow, Pacific Reef Egret, Eurasian Whimbrel, Barn Swallow and Collared Kingfisher.

In the evening we discussed with the head of the fishermen group of Harapan island. Apparently most of the fishermen in Harapan island already understand the role and importance of seabirds, mainly helping them in finding fish locations. According to them, seabirds accidentally enter their fish nets. From the statement we ask to immediately release if in the future there are seabirds who accidentally enter into the net or fish trap.

15 October 2017 at 09.00 am we left for Tanjung Pakis while recording and counted the seabirds along the way. No new species were found. Around 02.00 pm we arrived at Tanjung Pakis and the activity in this month is over. Will be done again per month until December 2017.

Systematic List:

  • Christmas Island Frigatebird | Fregata andrewsi
  • Great Frigatebird | Fregata minor
  • Lesser Frigatebird | Fregata ariel
  • Little Black Cormorant | Microcarbo niger
  • Greater Crested Tern | Thalasseus bergii
  • Lesser Crested Tern | Thalasseus bengalensis
  • Common Tern | Sterna hirundo
  • Black-naped Tern | Sterna sumatrana
  • Brown Noddy | Anous stolidus
  • Oriental Darter | Anhinga melanogaster
  • Glossy Ibis | Plegadis falcinellus
  • Swinhoe’s Storm-petrel | Hydrobates monorhis
  • Slender-billed Crow | Corvus enca
  • Pacific Reef Egret | Egretta sacra
  • Eurasian Whimbrel | Numenius phaeopus
  • Barn Swallow | Hirundo rustica
  • Pacific Swallow | Hirundo tahitica
  • Collared Kingfisher | Halcyon chloris
  • Common Sandpiper | Actitis hypoleucos

References:

TIRTANINGTYAS, F.N & HENNICKE, J. 2015. Threats to the critically endangered Christmas Island Frigatebird Fregata andrewsi in Jakarta Bay, Indonesia, and implications for reconsidering conservation priorities. Marine Ornithology 43 (2015): 137-140.

TIRTANINGTYAS, F.N & KHALEB, Y. 2017. Updating the Seabird Fauna of Jakarta Bay, Indonesia. Marine Ornithology 43: 137-140. Marine Ornithology 45 (2017): 11–16