Editing Amazon river dolphin (section)

===Habitat and migration===
The Amazon river dolphin is located in most of the area's aquatic habitats, including; river basins, major courses of rivers, canals, river tributaries, lakes, and at the ends of rapids and waterfalls. Cyclical changes in the water levels of rivers take place throughout the year. During the dry season, dolphins occupy the main river channels, and during the rainy season, they can move easily to smaller tributaries, to the forest, and to floodplains.<ref name=bebej/>

Males and females appear to have selective habitat preferences, with the males returning to the main river channels when water levels are still high, while the females and their offspring remain in the flooded areas as long as possible; probably because it decreases the risk of aggression by males toward the young and predation by other species.<ref name=bebej/>

In the [[Pacaya-Samiria National Reserve]], Peru, photo-identification is used to recognize individuals based on pigmentation patterns, scars and abnormalities in the beak. 72 individuals were recognized, of which 25 were again observed between 1991 and 2000. The intervals between sightings ranged from one day to 7.5 years. The maximum range of motion was {{convert|220|km|mi}}, with an average of {{convert|60.8|km|mi}}. The longest distance in one day was {{convert|120|km|mi}}, with an average of {{convert|14.5|km|mi}}.<ref>{{cite journal|last1=McGuire|first1=TL.|last2=Henningsen|first2=T.|year=2007|title=Movement Patterns and Site Fidelity of River Dolphins (''Inia geoffrensis'' and ''Sotalia fluviatilis'') in the Peruvian Amazon as Determined by Photo-Identification |journal=Aquatic Mammals|volume=33|issue=3|pages=359–367|doi=10.1578/AM.33.3.2007.359|bibcode=2007AqMam..33..359M }}<!--|access-date=22 November 2015--></ref> In a previous study conducted at the center of the Amazon River, a dolphin was observed that moved only a few dozen kilometers from the dry season and wet season. However, three of the reviewed 160 animals were observed over {{convert|100|km|mi}} from where they were first registered.<ref name=Silva/> Research in 2011 concluded that photo-identification by skilled operatives using high-quality digital equipment could be a useful tool in monitoring population size, movements and social patterns.<ref>{{Cite journal|last1=Gomez-Salazar|first1=Catalina|last2=Trujillo|first2=Fernando|last3=Whitehead|first3=Hal|date=2011|title=Photo-Identification - A Reliable and Noninvasive Tool for Studying Pink River Dolphins, Inia geoffrensis|url=http://whitelab.biology.dal.ca/hw/Gomez_photoID_Aquatic_mammals.pdf|journal=Aquatic Mammals|volume=37|issue=4|pages=472–485|doi=10.1578/am.37.4.2011.472|bibcode=2011AqMam..37..472G }}</ref>