Full/better quality map can be found here, you can also zoom in to read some of the text.
NI MOB MAP

MOB WAVE LOCATIONS

Screecher Mob wave event 

/wp [Next Island, 133336, 85176, 124, Screecher wave] 

(8 waves no boss)

Papoo waves

Yellow

/wp [Next Island, 137284, 83436, 112, Yellow papoo wave]

(ends with king on last wave)

Red

/wp [Next Island, 137752, 83181, Red papoo wave] 

(ends with king on last wave)

Brown

/wp [Next Island, 137505, 83991, 147, Brown papoo wave]

(ends with king on last wave)

Grey

/wp [Next Island, 136875, 83875, 109, Grey papoo wave 1]

(ends with king on last wave)

/wp [Next Island, 137939, 84295, 181, Grey papoo wave 2]

(does NOT end with a boss)

Village Boar

6 waves no boss

/wp [Next Island, 136698, 86875, 131, Village Boar]

 

NI BOSS SPAWN LOCATIONS

(I don't have all the locations or information on the Next Island bosses... yet)

Chillwing

(spawns after killing a lot of Snow Drakes)

/wp [Next Island, 136116, 93172, 717, Waypoint]

Flametounge

(spawns after killing a lot of Vulcan Drakes)

/wp [Next Island, 133031, 91365, 168, Waypoint]

Tempest

(spawns after killing a lot of Storm Drakes)

/wp [Next Island, 135612, 95369, 299, Waypoint]

Megladon 

(spawns after killing a lot of Great White Sharks)

/wp [Next Island, 129229, 91104, 101, Waypoint]

Bolker

(unclear when or what causes it to spawn- My guess is after so many Village Boars have been killed)

/wp [Next Island, 127945, 86873, 104, Bolkers Hideout]

Racc

(unclear when or what causes it to spawn- My guess is after so many Male Screechers have been killed)

/wp [Next Island, 135387, 86131, 223, Racc's Hideout]