Airlines, hotels, cruise lines, and tour operators are some of the biggest polluters in the world due to the global scope of the travel industry. And the vast majority travel companies have never reported on the sustainability of their operations.

A report from the World Travel & Tourism Council (WTTC) details the lackluster job travel companies around the world are doing of merely owning up to their effect on the environment.

Research in the “Environmental, Social & Governance Reporting in Travel & Tourism: Trends, Outlook and Guidance” report shows that just 13 percent of global travel companies have ever reported on their sustainability. The group worked with more than 20 of its members and travel industry partners to produce the report.

Since reporting isn’t mandatory for these companies, they have little incentive to make their impact on the environment public. But with the signing of the groundbreaking climate change agreement in Paris, companies will need to be more transparent when reporting on sustainability.

“After the Paris COP21 agreement, which puts a legally-binding obligation on countries to prepare plans to alleviate climate change, it is more important than ever that companies – in any industry – are able to evaluate their environmental impact before taking any relevant steps,” said World Travel & Tourism Council president and CEO David Scowsill. “However, companies do not always know how to report on their sustainable practices or are aware of which laws and regulations are in place and the obligations which they bring.”

Even the industries that are outperforming other travel industry peers in terms of reporting are insignificant when compared to the scope of the global travel industry.

“By way of example, over 30 airports have published sustainability reports, which would make them a significant group of reporters in Travel & Tourism in aggregate when compared to… other industries,” reads the report. “On the other hand, if compared with the hundreds of airports in existence, they would represent the smallest share of reporters within their respective universe.”

WTTC members, however, are doing a better job of reporting on sustainability than the travel industry overall. Eight out of 10 airline members report on sustainability, along with two out of six cruise lines and 21 out of 35 hotel members.

According to WTTC’s numbers, there are a total of 226 airlines, 323 lodging providers, and 89 cruise lines in the world, making WTTC members a minuscule portion of the overall travel industry.

There is incremental positive news about travel industry transparency on sustainability reporting. More companies are reporting compared to a decade ago, even if there is much more work to do.

Photo Credit: Pollution in Haiti. Alex Proimos / Flickr