New record of Carcharhinus leucas (Valenciennes, 1839) in an equatorial river system

Abstract

Bull sharks are a cosmopolitan shark species frequently found in shallow shelf ocean waters and, occasionally, in several tropical river systems around the world. Due to bull shark's capability to enter riverine systems, the documentation of its occurrence is essential for future fisheries inspections and studies. In this way, this study aims to report the presence of a medium sized specimen of C. leucas in an equatorial river system. The specimen was caught by fishermen at Mearim River, located in Northern Brazil and well known for the occurrence of tidal bores during the highest spring tides of the dry season. The event coincided with the occurrence of one of the strongest spring tides of 2015. The captured female specimen measured approximately 1300 mm and weighted 35 kg. The occurrence of this species was not known in this river basin until now. We recommend and support future ichthyologic studies in the Mearim River basin in order to provide data for the delimitation of the territory used by C. leucas in Maranhão State, specially looking into its age, growth, diet, spatial, and temporal movement patterns in this area.

First inland record of bull shark Carcharhinus leucas (Carcharhiniformes: Carcharhinidae) in Indonesian Borneo

“…A worlwide of global freshwater records of the C. leucas was compiled by Gausmann (2018). Previous known incidences presence of the C. leucas in freshwater area from around the world are: a freshwater record of 120 km inland in Zambesi River, Zimbabwe; recorded up to 420 km inland in Karun River, Iran; recorded of up to the distance of 130 km far inland in Lake Jamur, West Papua, Indonesia; a confirmed as far as 115 km inland at Wyrallah, Richmond River, Australia; a female C. leucas was reported in the Mearim River, 80 km far from the river's mouth, Maranhão State, Brazil; 67 juveniles C. leucas were monitored in Caloosahatchee River between 2003 and 2006 using 25 acoustic receivers, ranged 0 to 14 km with most more 5 km from the river's mouth, southwest Gulf Coast of Florida, United States; and recently a record of up to 75 km inland in Musi River, South Sumatra, Indonesia (Martin 2005;Heupel et al 2010;Feitosa et al 2016;Gausmann 2018;.…”

First photographic inland records of bull shark Carcharhinus leucas (Carcharhiniformes: Carcharhinidae) in Sumatran waters, Indonesia

“…The size of two juveniles of C. leucas in Musi River are meet to other records of the juveniles of this species from around the world, including presence of very young C. leucas in Brisbane River, Australia, range from 65-83 cm TL, and the 14 small specimens of C. leucas in brackish Indian River lagoon system on the central east coast of Florida, USA, ranged from 73-85 cm TL (Snelson et al, 1984;Pillans, 2006). The captured adult female specimen from inland of Mearim River, Brazil, measured approximately 130 cm (Feitosa et al, 2016). Further study and monitoring is needed to looking at the importance of Musi River basin as nursery area of C. leucas in western Indonesian waters.…”

“…A Synopsis of global freshwater occurrences of the C. leucas was summarized by Gausmann (2018). Some examples of the presence of the C. leucas in rivers from other parts of the world are: a inland record of 120 km up the river in Zambesi River, Zimbabwe; reported up Ecologica Montenegrina 22: 171-176 (2019) This journal is available online at: www.biotaxa.org/em to 420 km inland in Karun River, Iran; a record of approximately 130 km far inland in Lake Jamur, West Papua, Indonesia; a verified as far as 115 km from the sea at Wyrallah, Richmond River, Australia; a female C. leucas was caught by local fishermen in the Mearim River, 80 km far from the river's mouth, Maranhão State, Brazil; daily activity spaces of 67 juvenile C. leucas were monitored in Caloosahatchee River between 2003 and 2006 using an array of 25 acoustic receivers, ranged 0 to 14 km with most <5 km from from the river's mouth, southwest Gulf Coast of Florida, United States (Martin, 2005;Heupel et al, 2010, Feitosa et al, 2016Gausmann 2018).…”

VARIAÇÃO MORFOLÓGICA EM DENTES ROSTRAIS DO ESPADARTE EXTINTO ATLANTICOPRISTIS EQUATORIALIS PEREIRA & MEDEIROS, 2008.

“…Também foram considerados os índices de constrição (IC) e Índice de compressão do pedúnculo (ICP). da espécie Carcharhinus leucas (Feitosa et al, 2016). As duas condições são perfeitamente aceitáveis, pois estes padrões são registrados para as espécies viventes em ambientes atuais (e.g.…”