presence of whale sharks based on oceanographic variations in Cenderawasih Bay National Park, Papua, Indonesia

Abstract

Abstract. Manuhutu JF, Wiadnya DGR, Sambah AB, Herawati EY. 2021. The presence of whale sharks based on oceanographic variations in Cenderawasih Bay National Park, Papua, Indonesia. Biodiversitas 22: 4948-4955. Oceanographic factors have an important role in the study of estimating the distribution of fish resource habitats. Sea Surface Temperature (SST), Sea Surface Chlorophyll (SSC), Current Speed, Sea Surface Height (SSH), and bathymetry are important parameters that have been used in estimating the habitat of certain species. Through analyzing these environmental factors, research on the appearance and distribution of whale shark habitats in the Cenderawasih Bay National Park in Papua, Indonesia, utilized field observation data and satellite imagery. This study applied data on the presence of whale sharks and oceanographic parameter data from satellite recordings during 2019 – 2020. Analysis of the relationship and habitat modeling between the monthly presence of whale sharks and environmental parameters was carried out through the Generalized Additive Model (GAM) statistical approach and spatial analysis through the Geographic Information System approach. In the GAM analysis, data on the presence of whale sharks was used as a response variable. In contrast, the predictor variables consisted of SST, SSC, current speed, SSH, and bathymetric data. The results showed that the highest frequency of whale shark presence occurred in the transitional monsoon, with an average presence of 31.77 ± 4.00 %. The study also showed that all predictors showed a highly significant relationship (P < 0.001) to the number of whale sharks present. SST values range from 30.3 – 31.3 °C, SSC of 0.39 – 0.86 mg/L, the current speed of 0.46 – 0.65 m/s, SSH showed 0.63 to 1.00 cm, and bathymetry between 40 – 50 m . In the GAM model, the SST and SSC parameters were the two most important parameters that affect the presence of whale sharks, followed by SSHD, depth (bathymetry), and current parameters.

Seasonal Constellation of Juvenile Whale Sharks in Gorontalo Bay Coastal Park

“…The result of Pearson analysis showed that there is a negative, very low correlation between the yearly average of whale shark appearance and yearly average chlorophyll-a concentration (r=0,029) (Figure 8), while there is a positive, low correlation between yearly average whale shark appearance and yearly average SST (r=0,279) (Figure 9). These findings are contrary to the study of Manuhutu et al (2021) which used the Generalized Additive Model (GAM) analysis of the presence of whale sharks in the waters of Cenderawasih Bay National Park, Papua, Indonesia, the oceanographic parameters that have the most influence are Sea Surface Temperature (SST) and Chlorophyll-a and indicated that there are several other oceanographic factors influenced the whale shark's appearance in Botubarani waters, such as Sea Surface Height Distribution (SSHD) and depth (Bathymetry). Since the oceanographic conditions in Indonesia are diverse and complex, further study is important to draw a firm conclusion.…”

“…Meanwhile, juvenile whale sharks tend to be found congregating in shallow waters near the coast (Dove and Pierce, 2021). In Indonesia, the whale shark is also found in Cenderawasih Bay, Papua (Manuhutu et al, 2021), Talisayan waters, Kalimantan (Himawan et al, 2017), and Probolinggo waters (Syah et al, 2018;Kapinangasih et al, 2022). Large adult whale sharks are rarely found on the coasts because of their diving abilities and adaptations that allow them to obtain more prey in deep waters (Dove and Pierce, 2021).…”

“…In general, the seasonal constellation of whale sharks is influenced by oceanographic processes such as sea surface temperature, coastal currents, and increased productivity of the surrounding environment, particularly the abundance of phytoplankton (Heyman et al, 2001;Fox et al, 2013). In the Kwatisore waters of Cendrawasih Bay National Park, the seasonal constellation of whale sharks follows a fluctuating trend of increasing chlorophyll-a values and sea surface temperature (Enita et al, 2017;Manuhutu et al, 2021). Similarly, research carried out by Sakuntala et al (2016) on the emergence of whale sharks based on environmental factors in Probolinggo waters demonstrated that surface temperature and chlorophyll-a influence the pattern of whale sharks appearance.…”

Biological aspect approach in sustainable management of coral catshark Atelomycterus marmoratus (Anonymous [Bennett], 1830) in Bali Strait, Indonesia

“…In contrast, in Cenderawasih Bay National Park, SST and SSC parameters are the two most critical characteristics influencing the presence of whale sharks, followed by SSHD, depth (bathymetry), and current parameters. On the other hand, human activities affecting fish and their habitats, such as fishing and tourism, are accountable for declining whale shark populations (Anna and Saputra 2017;Manuhutu et al 2021). A previous study conducted by Md-Zain et al (2018a) demonstrated that 88.2% of individuals were found in a local market in Malaysian Borneo where sharks were endangered (Lamiopsis tephrodes, Sphyrna mokarran, and Sphyrna lewini), vulnerable (Alopias pelagicus and Rhynchobatus australiae), and near threatened (Carcharhinus limbatus, griseum, Carcharhinus sorrah, and Carcharhin).…”

Seasonal Migration Zone of Skipjack Tuna (Katsuwonus pelamis) in the South Java Sea Using Multisensor Satellite Remote Sensing

“…A horizontal line at zero indicates no parameter effect. GAM function modeling above the zero axis indicated a strong (positive) influence of a parameter and vice versa [25].…”