Consider the following statements:
1. Both Ganges River dolphins and Irrawaddy dolphins have a gestation period of more than one year.
2. Indus and Ganges River dolphins are found in freshwater whereas Irrawaddy dolphins can be found in brackish water.
3. Unlike Indus River dolphins, Ganges River dolphins are functionally blind.
4. Indus River Dolphins, Ganges River Dolphins and Irrawaddy Dolphins species are listed as Endangered on the IUCN Red List of Threatened Species.
Which of the statements given above are correct?