true

ISRA FACTSHEETS

NEW ZEALAND & PACIFIC ISLANDS REGION

ISRA FACTSHEETS

NEW ZEALAND & PACIFIC ISLANDS REGION

Peleliu Corner ISRA

131/179

Peleliu Corner ISRA

Peleliu Corner

Summary

Peleliu Corner is located in Peleliu, Palau. This area is characterised by a vertical wall, crevices, and canyons with sandy substrate. The wall is covered with hard corals and rock rubble. This area is where the ocean currents flowing around this island archipelago converge. Within this area there are: threatened species (e.g., Bull Shark Carcharhinus leucas); feeding areas (e.g., Blacktip Shark Carcharhinus limbatus); and undefined aggregations (Grey Reef Shark Carcharhinus amblyrhynchos).

Peleliu Corner

Peleliu Corner

DESCRIPTION OF HABITAT

Peleliu Corner is located in Peleliu, Palau. The reef is a vertical wall that runs parallel to the southernmost tip of Peleliu Island and encompasses the dive sites known as ‘Peleliu Corner’, ‘Peleliu Cut’, and ‘Peleliu Wall’ (Harel-Bornovski & Bornovski 2015). The upper end of the wall is characterised by crevices and canyons with sandy substrate. The wall gradually drops from 7–40 m and is covered with hard corals and rock rubble. At ~33–40 m the reef forms a plateau before dropping off again to hundreds of metres (Harel-Bornovski & Bornovski 2015). While incoming tides flow to the northeast, outgoing tides flow to the southwest. During full and new moon events, the currents are more severe because of the tide (Harel-Bornovski & Bornovski 2015). The area is renowned for strong currents and upwelling, as the strong currents coursing between Angaur and Peleliu hit both those islands, due to a submarine ridge between them (Colin 2009).

This Important Shark and Ray Area is benthic and pelagic and is delineated from surface waters (0 m) to 50 m based on the bathymetry of the area.

CRITERION A

VULNERABILITY

Three Qualifying Species considered threatened with extinction according to the IUCN Red List of Threatened Species regularly occur in the area. These are the Endangered Grey Reef Shark (Simpfendorfer et al. 2020); and the Vulnerable Bull Shark (Rigby et al. 2021a) and Blacktip Shark (Rigby et al. 2021b).

CRITERION C

SUB-CRITERION C2 – FEEDING AREAS

Peleliu Corner is an important feeding area for two shark species.

Between 2013–2024, assemblages of Bull Sharks (n = ~4 individuals) and Blacktip Sharks (n = 2–10 individuals) were reported each year feeding on Sailfin Snapper Symphorichthys spilurus and Two-spot Red Snapper Lutjanus bohar spawning aggregations in the area (Sakaue et al. 2016). Sailfin Snapper spawning events occur regularly and predictably between March–May for 4–5 days during the waxing moon phase (between the full moon and the new moon), from dawn until 10 am (Sakaue et al. 2016). Two-spot Red Snapper spawning occurs early morning every month throughout the year, just after the quarter moon until a few days before the full moon (Sakaue et al. 2016).

Observations of sharks feeding on spawning aggregations occur during 70% of dives in the area during the spawning events (J Alpert pers. obs. 2013–2024). Additional records are available from recreational divers who shared photos/reports on social media channels in 2017, 2021, 2023, and 2024. Blacktip Sharks are regularly observed actively hunting, whereas Bull Sharks cruise around, opportunistically feeding. These assemblages are not seen in this area during the rest of the year, nor are either of these shark species seen in similar numbers (J Alpert pers. obs. 2013–2024).

CRITERION C

SUB-CRITERION C5 – UNDEFINED AGGREGATIONS

Peleliu Corner is an important area for undefined aggregations of one shark species.

Between 2009–2024, this area was regularly visited by recreational divers. Dives in the area occurred once a month, except during the Sailfin Snapper spawning event (March–May) when dives occur ~4 times a month. Aggregations of 10–80 (average = ~15) Grey Reef Sharks are regularly and predictably observed (~90% of the dives) near the reef wall, year-round, mostly between 10–50 m (T Harel-Bornovski pers. obs. 2009–2024). Based on shark counts by dive guides from 2007–2012, aggregations ranged between 3–80 (average = 11.6) Grey Reef Sharks (T Harel- Bornovski unpubl. data 2012). Additional records are available from recreational divers who shared photos/reports on social media channels in 2012, 2013, and 2019. Peleliu Corner has strong currents and current strength was positively correlated with the abundance of Grey Reef Sharks in Palau (Vianna et al. 2013). However, further information is required to understand the regularity and function of this aggregation.

Peleliu Corner

SUBMIT A REQUEST

ISRA SPATIAL LAYER REQUEST

To make a request to download the ISRA Layer in either a GIS compatible Shapefile (.shp) or Google Earth compatible Keyhole Markup Language Zipped file (.kmz) please complete the following form. We will review your request and send the download details to you. We will endeavor to send you the requested files as soon as we can. However, please note that this is not an automated process, and before requests are responded to, they undergo internal review and authorization. As such, requests normally take 5–10 working days to process.

Should you have questions about the data or process, please do not hesitate to contact us.

    * indicates required

    Industry or sector (*)

    Under the terms and conditions of our User License Agreement , full and appropriate acknowledgement is required in any materials and publications derived from the data (and copies should be sent to the IUCN SSC Shark Specialist Group through the contact form). For any publications making substantial use of the data, the ISRA welcomes the opportunity for co-authorship, collaboration, and to comment prior to publication.


    Furthermore, we need to know whether you are a commercial or non-commercial user. Non-commercial includes scientific research, education or conservation. Commercial is defined as follows: any use by, on behalf of, or to inform or assist the activities of a commercial entity (that operates ‘for profit’) or use by a non-profit for the purposes of revenue generation

    Type of use(*):

    Please specify which layer (ex. all layers, layers within a specific Region, layers within a Jurisdiction or a single ISRA): Purpose (*):

    Please provide a description of how you intend to use the ISRA GIS Dataset. The more details you provide, the faster we can respond to your request. We may require further clarification prior to providing access. (min. 100 characters – max 1,000 characters)



    File format request (*)

    By providing your personal data, you consent to its processing as described below. The IUCN SSC Shark Specialist Group will use the information you provide on this form to send the documents you requested. You can change your mind at any time by writing to the ISRA Data Coordinator www.sharkrayareas.org/contact. All personal details provided will be treated with respect. For any information you can visit our Privacy Policy.
    Please read the User License Agreement and ISRA Layer Metadata Description

    This form uses Google reCaptcha to reduce spam. Privacy - Terms