Without water, there is no life. Water conservationist Rajendra Singh is bringing dead streams back to life in India. Thousands of dead fish have turned up in the Rhine River in Switzerland — fish are vulnerable to high temperatures as their environment heats up. And, an entrepreneur wants to drag icebergs all the way to South Africa!

Just how many visitors are too many? The Greek island of Santorini struggles with tourism numbers it can't handle. How long until rising sea levels have completely destroyed Kenya's historic sites along its coast? And how hot is too hot? Glaciers in New Zealand have receded so much it's actually become too dangerous to hike all the way to the top.

It's hot out there. The heat wave sweeping across the northern hemisphere this week has farmers worried, especially where the high temperatures are combined with drought. We look at how farmers around the world are protecting their livestock and crops as the global temperature creeps ever higher.

Tarantulas, scorpions and cockroaches are not appealing — but they are important! Eels in Canada are being chopped up by dams — but they don't get the attention they deserve because they aren't cute like pandas. Poisonous scorpions are more important for our ecosystem than you may have thought. And a taste for tarantula in Cambodia has decimated their numbers.

When it comes to protecting the environment, sometimes the most unusual ideas are the best ones. From using donkey dung to help save an endangered bat to brewing beer out of old bread, we examine some of the strange and innovative ways people are helping save the planet.

Shoot to kill or live and let live? We're not always kind to animals, unless perhaps they're in a zoo. We'll get up close and personal with a zebra finch and find out why Germans really love their bears.

Women in Saudi Arabia made the headlines this week. They are now allowed to drive, thanks not least to the campaigning by some bold women. In this week's episode, we'll meet some other bold women: Abu Dhabi's first female falconer, an Indian activist fighting plastic pollution, an Italian investigative journalist uncovering a mozzarella scandal and a Canadian diver exploring underwater mysteries.

Most people think of insects as pests to get rid of — but our survival may be intimately tied to them. The problem is: Insects are in decline. Find out how the Berlin Philharmonic is drawing attention to the issue, why insects don't live at the seaside, and what makes bugs so important in the first place.

We live on a planet of finite resources but our demand for new consumer products and technologies keeps growing. That's driving a race to extract materials from ever-more remote corners of the Earth – and beyond.

Ever more people in the world are living in urban areas. But how can we make our cities sustainable? From the dangers of air pollution to shrinking natural spaces and our carbon footprint in cities — it's high time for action.