Only one sighting of two individuals of Steno bredanesis in the Swatch of No-ground (165 km offshore on the south from the Sundarbans) was observed by BCDP in 2012 (BCDP Unpubl.). No more information is available to assess this species. Thus, it is categorized as Data Deficient.

Little is known about the distribution and population size of Stenella longirostris in Bangladesh. Fourteen sightings Stenella longirostris in the northern tip of Swatch of No-ground were reported by BCDP (2008) with mean group size 85. There was no more information available from other marine waters of the Bay of Bengal in Bangladesh territory. Thus it is categorized as Data Deficient.

There are only two sightings of Pseudorca crassidens have been reported: first one with about 30 individuals in the Swatch of No-ground in 2011, and second one with about 40 individuals in the offshore south of S. Martin's Island in 2012. One carcass was reported in the Daily Azadi newspaper of Chittagong on 28 December, 2010. There is no information available on its population size, threats or population trend. Thus, the species has been assessed as Data Deficient.

There is no record of Sperm Whale occurrence in Bangladesh except one carcass that was found in 22 November, 2007 at the Selarchar of Sundarbans East Wildlife Sanctuary in the southern coast of Bangladesh (The Daily Purbanchal, 28 November 2007 and The Daily Star, 30 November 2007) that was brought ashore by the tidal surge Sidr that badly impacted Bangladesh western coast. No more information is available to assess this species. Thus it is categorized as Data Deficient.

In February 1985, a 13.7 meter long carcass of Balaenoptera sp. was found in the south coast of Cox's Bazar (Sarker 1990). Carcass of Brydes Whale was also found at Mandarbaria on the southwest coast of the Sundarbans in February 2008, and another carcass was found at coast of Barguna district in March 2014. During December 2006 to February 2007, forty sightings of Balaenopterids occurred in and arround the Swatch of No-ground with mean 2.9 individuals (range 1-15) of which six were confirmed Bryde's Whale sightings from photo identification (Smith et al. 2008a). Thus, Bryde's Whales are believed to be distributed throughout the offshore in the Bay of Bengal but there is no estimation of its population size as well as population trends. Thus, this species has been categorized as Data Deficient.

Though this species is widely distributed in diverse habitats, the population has been declining due to retribution killing, hunting for meat, road-side killing and other anthropogenic factors. It has been categorized as Near Threatened based on its level of threats.

There are some intervening information on the presence of this species but appropriate data on abundance and/ or distribution are lacking. Therefore, it is categorized in Data Deficient.

Although the name of Bangladesh mentioned as the westernmost range of the species (Duckworth et al. 2008, Khan 2009), there is no report confirming its occurrence in Bangladesh. However, it is expected to occur in mixed evergreen in the northeast and southeast of Bangladesh. In the absence of any concrete proof of occurrence the species has been categorized as Data Deficient.