Britain and Canada on Monday joined the European Union in pledging to protect 30% of their land and seas by 2030 to stem "catastrophic" biodiversity loss and help galvanise support for broader agreement on the target ahead of a U.N. summit. With the twin crises of climate change and wildlife loss accelerating, leaders are trying to build momentum ahead of the meeting in Kunming, China, in May, where nearly 200 countries will negotiate a new agreement on protecting nature. Without action, 30% to 50% of all species could be lost by 2050, threatening economic and social prosperity, a report by The Nature Conservancy charity this month said.