Why are our Ana's dying?

For reasons unknown, Ana trees are dying off in the west of the country, leaving experts puzzled but with a variety of theories.

01 October 2018 | Environment

Hundreds of dead Ana tree trunks dot large areas of the Ugab, especially upriver from the Brandberg massif. In the last couple of years, scientists have established that up to 79% of Ana trees in the Swakop River have died. Scientists have witnessed the same trend in the Kuiseb River.

“Naturally it is very sad,” said prof. Nico Smit who works as a specialist in animal husbandry and grazing at the University of the Free State. “Although I have no answers, I do have several theories, because we observed a similar phenomenon in camelthorn trees,” he said.

Ana trees mainly grow in rivers and streams in the north-western regions of the country. According to the well-known zoologist Barbara Curtis, tall trees tower between ten and twenty meters in height, while the trunks of old trees can be more than a meter in diameter. The taproot also grows up to 40 meters below ground, consequently these trees can easily tap water from aquifers in rivers.

“In a survey carried out in the Swakop River, students from Gobabeb found that between 67% and 79% of trees there had died, in comparison to 4% in the Kuiseb,” she said. The students also found no cause for the die-back. “Perhaps it could be that the groundwater level has sunken. This could be true in the Swakop River because there are many dams and boreholes along its course, but it cannot be the case in the Ugab,” she said.



Old age?

According to Smit, “Many of these trees, which died in a relatively short period of time, are quite old and are most likely of a similar age”.

These trees grow in dry riverbeds and could have survived repeated years of extreme or unfavorable environmental conditions, including droughts. “However, in time these trees are no longer able to survive in these harsh conditions given their age or natural senescence,” he explained.

In this context, he recalled a long and especially severe drought that hit large parts of southern Africa a few years back. Consequently the groundwater in some rivers have fallen substantially. However, he is convinced that younger trees would have survived this, describing such extreme conditions as normal because it happens ever so often.

“Because of climate change, however, such extremes are aggravated and more extreme. It is striking that between the old, dead trees, no young trees seem to grow,” he said. Since no younger trees are replacing the old ones, the die-backs are particularly noticeable, according to Smit.

In addition to this theory, Smit can't rule out an infection, such as a fungal disease, that could have contributed to the trees dying.

Well-known Namibian botanist Coleen Mannheimer sees it in a similar light. “I think it's a fatal combination of a high parasite infestation and drought that has weakened the trees,” she said. “It is cause for concern.”

Similar News

 

Cacti infestation out of control

1 month - 03 December 2018 | Environment

Yolanda Nel - Large areas of the capital have already been infested with three cactus species that are preventing other natural plants from growing.“Several alien...

Looking at the looting of logs

1 month - 03 December 2018 | Environment

On Tuesday (4 December), the Scientific Society hosts a public talk by John Grobler themed Let's Look at the Looting of Logs.Between 1990 and 2000,...

Boost for recycling and job creation

1 month - 03 December 2018 | Environment

With job creation stagnant and e-waste problems increasing, the company NamiGreen has begun with operations throughout the country with twin goals in mind: To jump-start...

Insects to control infestation

2 months ago - 19 November 2018 | Environment

Yolanda Nel - Large areas of the capital have already been infested with three specific cactus species that are preventing other plants from growing.For this...

Say no to straws!

2 months ago - 19 November 2018 | Environment

When the tourism industry launched its “Joining hands, linking brands for a cleaner Namibia” initiative in December last year, they could only hope that the...

Climate-­friendly technologies adopted

2 months ago - 19 November 2018 | Environment

Namibia has made much progress in phasing out ozone-depleting substances and adopting ozone and climate friendly technologies.According to the minister of industrialisation, trade and SME...

Pangolins take centre stage

2 months ago - 19 November 2018 | Environment

The pangolin, also known as the scaly anteater, is the world's most trafficked wild animal. Its body parts are sold in Asia – mainly China...

Making Namibia greener - online

2 months ago - 12 November 2018 | Environment

Yolanda Nel - The Recycle Namibia Forum (RNF) is excited to introduce the very first Green Directory. Even better news is that it is available...

Cacti gotta go

2 months ago - 29 October 2018 | Environment

A successful cactus clean-up campaign was held in Sinclair Street in the capital last Saturday, where a number of NEWS members, staff from Matiti Safaris,...

A step towards sustainable energy transformation

2 months ago - 29 October 2018 | Environment

“We are opening up a window of opportunity for the entire SADC region,” said Namibian minister of mines and energy, Tom Alweendo, at the inauguration...

Latest News

Watertoevoer bly 'n uitdaging

19 hours ago | Infrastructure

Op Groot Aub sê inwoners hulle gaan soms dae lank sonder water.Tydens 'n onlangse onderhoud met Nampa, het inwoners van die ne-dersetting wat sowat 45km...

Women at Work trains nannies

19 hours ago | Education

A number of women from Farm Skoonheid near Gobabis recently received training to become nannies to better their knowledge and skills to take care of...

Just enough better than more

19 hours ago | Banking

As the economy begins to improve, entrepreneurs will find greater confidence to establish SMEs, while existing SMEs will seek finance to grow, says Jerome Mutumba,...

Artist group struts their stuff

19 hours ago | Art and Entertainment

A group exhibition by the Ileni Pamwe Project of Visual Artists opened at the Omba Gallery in the capital last week.The exhibition showcases mixed media...

Shotgun at the Warehouse

19 hours ago | Art and Entertainment

Indie-folk singer and songwriter Shotgun Tori makes a Namibian comeback with her tour Where We Left It Off at the Warehouse Theatre.Blending folk, rockabilly, country...

Life in full colour

19 hours ago | Art and Entertainment

Running at the National Art Gallery in the capital until 16 February, is Of the Greatness of Life, a solo exhibition by Dr Helmut Lauschke.Consisting...

Events calendar

19 hours ago | Art and Entertainment

Currently running• Art Come Together, an exhibition of the results from art workshops in the Khomas, Kavango East, Oshana and Hardap regions at the National...

A new you in the...

19 hours ago | People

If you're looking for a rebrand in terms of your image, reputation, lifestyle or even habits but you're finding it hard to start, it might...

Support for soccer centre

19 hours ago | Society

The Namibia Football Association (NFA) Girls Centre last week received 18 single beds and bedding worth N$75 000 from the Deutsche Gesellschaft für Internationale Zusammenarbeit...

Load More