<Tr> <Td> 1915 </Td> <Td> 7 </Td> </Tr> <Tr> <Td> 1916 </Td> <Td> 14 </Td> </Tr> <Tr> <Td> 1917 </Td> <Td> </Td> </Tr> <Tr> <Td> 1918 </Td> <Td> 36 </Td> </Tr>

Where the lack of a natural predator in yellowstone