Gharial

Gharial (Gavialis gangeticus)
Attribution: Clpramod / CC BY-SA (https://creativecommons.org/licenses/by-sa/4.0), this image was modified from the original version. Image source.

Gharial (Gavialis gangeticus) were once found throughout river networks associated with the Indus, Ganges, Brahmaputra-Meghna, and Mahanadi rivers of the Indian subcontinent. Water pollution, habitat loss due to dams and water extraction from rivers, persecution by fishermen, entanglement in fishing nets, harvest of gharial eggs for human consumption, and hunting for skins have all played a role in the decline of this species. Gharial no longer occur in Bhutan, Myanmar, Pakistan, and river networks associated with the Indus River.
(Information summarized form Lang et al. 2019)

River networks associated with the Ganges, Brahmaputra, and Meghna rivers. The general location of the Mahanadi river basin is indicated in blue text.
Pfly / CC BY-SA (https://creativecommons.org/licenses/by-sa/3.0). This map was modified from the original version. Image source.

Indus River location (dark blue).
OpenStreetMap contributorsOpenstreetmap contributors / CC BY-SA (https://creativecommons.org/licenses/by-sa/2.0). Image source.

Today, gharial are found only in a handful of isolated regions within India, Bangladesh, and Nepal. Despite ongoing conservation efforts over the past several decades, which have included captive breeding and reintroductions, the species remains listed as critically endangered by the International Union for the Conservation of Nature (IUCN), but with numbers increasing in the wild (Lang et al. 2019).

Distribution of gharial (dark blue regions) according to IUCN Red List 2019  (Lang et al. 2019).
Image attribution: BhagyaMani / CC BY-SA (https://creativecommons.org/licenses/by-sa/4.0).This map was modified from the original version. Image source.

For more information on gharial conservation efforts:
IUCN Red List - Gharial
IUCN - Gharial conservation
WWF India - Gharial

Works cited
Lang, J, Chowfin, S. & Ross, J.P. 2019. Gavialis gangeticus (errata version published in 2019). The IUCN Red List of Threatened Species 2019: e.T8966A1492277430. http://dx.doi.org/10.2305/IUCN.UK.2019-1.RLTS.T8966A149227430.en

American bison

American bison (Bison bison)
Image attribution: Jack Dykinga / Public domain. Image source.

Prior to the 1800s, American bison (Bison bison) likely numbered in the tens of millions. Large herds roamed across much of Canada, the United States, and northern Mexico. During the 1800s, colonization of western America was accompanied by mass slaughter and exploitation of bison. By 1900, only a few hundred individuals remained and in small, isolated populations. Today, conservation efforts have restored bison herds at several locations in Canada, the United States and, more recently, Mexico. However, the vast majority of bison currently in the U.S. are members of captive herds maintained for commercial purposes.

Bison rage prior to 1720 (tan area), bison range as of 1870 (light brown area), and bison range as of 1889 (dark brown regions). Year of localized exterminations are indicated (light numbers), as well as population estimates for disjunct populations during 1889 (dark numbers).

Image attribution: Cephas / CC BY-SA (https://creativecommons.org/licenses/by-sa/3.0). Image source.

Locations of herds of plains bison (Bison bison bison, dark brown circles) and wood bison (Bison bison athabascae, tan rhombus) as of 2003. For a list of the named places indicated by this map, click here.

Image attribution: Cephas / CC BY-SA (https://creativecommons.org/licenses/by-sa/3.0). Image source.

For information on American bison conservation efforts:
American Prairie Reserve - Bison Restoration
National Park Service - Protecting Bison
Wildlife Conservation Society - The Future of Bison
World Wildlife Fund - Bison Facts
IUCN Red List - American Bison