A BAT and the blue spider

Hiking through the humming forest along Guyana’s upper Potaro River in the deep dark of night, the American herpetologist slowly swung his flashlight, scanning for secretive creatures. In the narrow but bright beam, he caught the unusual glimmer of brilliant blue, sticking out of a small hole in a rotting stump.

“At first I quickly dismissed it – surely it was just the eye shine coming from a spider. But something was different, and I must have been subconsciously aware. Something made me go back. And it is a good thing I did,” biologist, conservationist and photographer, Andrew Snyder recalled.

Originally tasked with discovering amphibians and reptiles, the experienced Snyder used visual cues to promptly process images, honed from years of nocturnal surveys. “For some organisms, like snakes, it is a certain body shape, and for others, it can be a glint of eye shine. Many jungle organisms give off eye shine, caused by the reflection of your beam of light off of a membrane in the eye, and typically with a characteristic colour depending on the organism. Certain species of tree boa, for example, give off an orange reflection, which is purplish-orange in moths, and green-blue in spiders,” he explained in a guest blog for sponsor Global Wildlife Conservation (GWC).

The iridescent electric blue that his torch picked up was not from orbs but the “cobalt” coloured forelimbs and broad abdomen band of a soda-sized, otherwise-black tarantula. “I have spent years conducting surveys in Guyana and have always paid close attention to the tarantula species. I immediately knew that this one was unlike any species I have encountered before,” he related.

One of the exciting finds during a 2014-successful survey known as the second Biodiversity Assessment Team (BAT) expedition, in which local and international researchers searched for new and little-known species in Guyana’s remarkably rich Kaieteur National Park (KNP) and the Upper Potaro District, the beautiful tarantula made multiple headlines. The team collected data on 10 taxonomic groups including birds, plants, large mammals and decapod crustaceans. More than 30 species that are likely novel, including a frog, several fishes, dragonflies, damselflies, and aquatic beetles were recorded in a detailed report released a year ago by the  World Wildlife Fund for Nature/Guianas (WWF/G), in collaboration with entities like GWC, the Guyana Protected Areas Commission (GPAC), the University of Guyana (UG) and the Patamona village of Chenapau.  

Snyder’s five-foot-tall tree stump in the primary forest was marked with numerous holes occupied by the blue tarantulas, implying that this may be a communal species, an uncommon behaviour in such spiders. Terming the arthropod “an incredible find,” he wrote “this brilliant tarantula should stand as a beacon for invertebrate conservation in Guyana.”

“Though often overlooked and not typically mentioned during conservation conversations, invertebrates are vital to the proper maintenance and function of ecosystems and are just as important as charismatic macrofauna. Hopefully a species like this can represent the flagship for invertebrate conservation and promote awareness for less appreciated taxa,” he said, highlighting the Potaro Plateau as a key transition zone for species between the lowlands and the highlands with high levels of endemism for many taxonomic groups.

Noting that some 85 per cent of Guyana’s landscape is still covered in rainforests, the WWF termed this the second highest proportion in the world, in terms of such percentage relative to a country’s total land mass, at a time when other places are experiencing large-scale biodiversity loss and environmental degradation. At the same time, Guyana’s biodiversity remains largely undocumented and poorly studied, leaving the government and indigenous communities with a paucity of data on which to base land-use planning decisions, the document pointed out.

Established since 1929, KNP sits on the Potaro Plateau of the Pakaraima Mountains, which are made up of some of Earth’s most ancient rock formations, about 1.7 billion years old. The Park harbours high levels of mammals, amphibians and birds, with significant levels of species endemism. Previous studies show that 44% of amphibians, 16% of mammals, 13% of reptiles, 12% of birds and 8% of plants in KNP are endemic to the wider region of the Guiana Shield and Guiana Highlands. Some species of herpetofauna and plants are possibly found nowhere else,  including the Kaieteur golden rocket frog which spends its entire life cycle in the giant tank bromeliad. Dividing the Park, the Potaro River thunders 741 feet as the famous Kaieteur Falls into the mist-filled gorge. Based on rough estimates, over one million little swifts are thought to roost behind the single drop falls, making it the world’s largest swift roost. These Kaieteur swifts or so-called Makonaima birds named for the legendary Amerindian Great Spirit or Creator God nest under the vast shelf of rock that has been carved out by centuries of erosion, hidden aback the cold brown curtain of falling water.  Large colonies of the Tepui Swift, the White-collared Swift, the Grey-rumped Swift and the Band-rumped Swift are found as well in the gorge and on cliffs along the plateau.

While visitors to the park have increased, the integrity of the area is threatened by gold mining activities, with illegal operations affecting habitats and species. The effects of mining on freshwater and terrestrial habitats are already visible, the report added, pointing to mercury and water pollution affecting local communities.

Urging the adoption of a range of recommendations, the WWF called for the strict enforcement of mining prohibition within the zone, through additional properly equipped rangers and weekly patrols; the restoration of abandoned mining areas; the development of alternative livelihoods for the indigenous people; and the provision of related educational programmes on the importance of the Park, clean water, and biodiversity to their health and welfare. Researching the level of mercury in people and the environment, including assessing the dangerous element in common food fishes, should be done to encourage behavioural change. The Fund stressed that demonstrations of mercury-free and responsible mining need to be made a priority, with related training on less environmentally harmful mining practices.

Research should be continued on the Park’s unique flora and fauna, the WWF insisted. In the words of Snyder, the BAT rapid inventory was able to reveal an important glimpse into this special area of Guyana, though far more work is necessary to shed light on the region’s many mysterious secrets – and spiders.

ID witnessed and walked among scores of giant tarantulas strolling in the moonlit yard of her Antiguan home. She does not suffer from arachnophobia and jokes that spiders communicate through the World Wide Web.