These 5 countries are the worst environmental offenders

Thomson Reuters

Each year, Yale's Environmental Performance Index (EPI) ranks 180 countries based on how well they've fared at protecting human health and vulnerable ecosystems. 

The EPI creates the index by giving each country a score out of 100 that's based on a number of specific metrics. The individual scores are averaged for each country to create the rankings.

The worst offending countries all share a few common traits. They're mostly impoverished, torn-apart by conflict, and have ongoing problems with drought and environmental degradation. 

We've brought you the top five countries. Now, here are the five worst offenders from the 2016 report:

#180 Somalia: 27.66

Somalia was the lowest-scoring country on the EPI for a good reason: the country has been mired in a decades-long conflict. Warring factions, like the terrorist group Al Shabaab, are constantly jostling for control. 

Somalia ranks 168th in health impacts, 176th in water and sanitation, 100th in fisheries, and 179th in biodiversity and habitat protection. 

The lack of firm authority has allowed piracy to flourish, and Somalia's unregulated fishery has decimated fish stocks along its coast. Many Somalians also lack access to clean water and safe sanitation. 

#179 Eritrea: 36.73

Eritrea narrowly beat Somalia to take the 179th spot. 66% of Eritreans live below the poverty line, and the country suffers from droughts and rampant famine. 

Eritrea ranks 160th in health impacts, 105th in air quality, 168th in water and sanitation, and 165th in biodiversity and habitat. 

Conflict is also an ongoing problem in Eritrea, and its army is often involved in border skirmishes with neighboring Ethiopia and Djibouti. 

But Eritrea is also rich in mineral resources, and the government hopes to build the economy through the mining sector. 

#178 Madagascar: 37.10

Madagascar took the third-lowest spot. Similar to Somalia, Madagascar is largely undeveloped, and is among the poorest countries in the world.

Madagascar ranks 178th on health impacts, 177th in water and sanitation, 130th in air quality, and 132nd in biodiversity and habitat. 

Despite Madagascar's low rank, Madagascar scored 20th on agriculture, likely because most Malagasies farm through traditional methods. 

Yet Madagascar is also one of the most biodiverse countries on the planet — claiming unique species found nowhere else on Earth — so protecting its environment from illegal logging operations is crucial.