Giant sea bass are thriving in Mexican waters – scientific research that found them to be critically endangered stopped at the US-Mexico border

Giant sea bass are listed as a critically endangered species.
Maru Brito, CC BY-ND

Arturo Ramírez-Valdez, University of California San DiegoI was looking at the seafloor, focused on identifying fish species as I normally did when diving off of the California coast, when suddenly I felt something large above me. When I turned my head I saw a giant fish – more than 6 feet (2 meters) long – calmly interested in the air bubbles coming from my SCUBA regulator. This was 2016 and was my first encounter with a giant sea bass.

I am a marine ecologist, and I study how international borders pose challenges for conservation and management efforts in the marine environment. Although there are no walls or fences in the ocean, borders still act as stark barriers for a variety of things.

Giant sea bass live off the west coast of North America in both Mexican and U.S. waters. I have found that large differences in regulation and research effort between the two countries has led to a significant misunderstanding of giant sea bass population health.

Giant sea bass live in coastal waters from northern California all the way south to the Sea of Cortez.
Arturo Ramiréz-Valdez, CC BY-ND

Different countries, different science

The giant sea bass is the largest coastal bony fish in the Northeastern Pacific. It can grow up to 9 feet (2.7 meters) long and weigh up to 700 pounds (315 kg). It lives in coastal waters from northern California to the tip of the Baja California peninsula in Mexico, including the entire Gulf of California.

In California, commercial fishing for the species began in the late 1880s. Large fish used to be very abundant across the entire range, but the fishery collapsed in the early 1970s. As a response, in 1981 the U.S. banned both commercial and recreational fishing for giant sea bass, and there are many ongoing research and population recovery efforts today.

The collapse and subsequent protection and flurry of research in the U.S. stand in stark contrast to Mexico. In Mexico, there are minimal regulations on fishing for the species, and there is almost a complete lack of data and research on it – there are only three studies on giant sea bass with any data from Mexico.

The International Union for Conservation of Nature considers giant sea bass to be a critically endangered species due to the population being “severely fragmented, leading to a continuing decline of mature individuals.” But this decision was based on a report that had no data whatsoever from Mexico. This lack of data is concerning, considering 73% of the species’ range is in Mexican waters.

This knowledge gap made me wonder if ecologists had the wrong idea about the health of giant sea bass populations.

Giant sea bass are a common sight at fish markets throughout Baja.
Proyecto Mero Gigante, CC BY-ND

Healthy fish in Mexico

In 2017, I led an effort to document the giant sea bass population in Mexico and look for clues to what it was in the past. At the beginning of the project, my colleagues and I feared that the records in Mexico would confirm the precarious situation of the fish in the U.S. But the reality turned out to be the opposite.

Commercial fishers don’t often target giant sea bass, but catch them as bycatch when fishing for other species.
Proyecto Mero Gigante, CC BY-ND

To our surprise, we found giant sea bass everywhere in the fish markets and fishing grounds from our very first assessments. The fishmongers were never out of the fish; instead, they would ask us, “How many kilos do you need?” It was clear that for fishers in Mexico, the species is still common in the sea, and therefore, in their nets. It is still possible to find big fish up to 450 pounds 200 kilograms, and the average catch was around 26 pounds (12 kilograms).

It was fantastic to see an abundance of these fish in markets, but I also wanted to understand the fishery trends through history and how current fishing levels compared to previous years. I looked at historical and contemporary fishing records and found that the Mexican commercial fleet has caught an average of 55 tons per year over the past 60 years, and the fishery has been relatively stable over the past 20 years, with a peak in 2015 at 112 tons.

According to U.S. and Mexican records, the largest yearly catch ever recorded for giant sea bass in Mexico was 386 tons in 1933. Biologists consider a fishery to have collapsed when total catches, under the same effort, are less than 10% of the largest catches on record. So a steady trend of 55 tons per year shows that the fishery in Mexico has not collapsed. It is clear that giant sea bass populations have faced severe declines throughout their range; however, the health of the species is not as dire as thought.

Another interesting finding from my research is that the apparent collapse of the giant sea bass fishery documented in the 1970s actually began as early as 1932.

Over the first half of the 20th century, as the U.S. commercial fleet overfished U.S. waters, they began fishing in Mexican waters too – but they continued to count all catches as from the U.S. This changed in 1968 when the two governments signed the Mexico–U.S. Fisheries Agreement, limiting how much fish each country’s fleet could take from the other country’s waters. The collapse of the U.S. fishery in the 1970s was not due to a drastic reduction in fish numbers in Mexican waters, but driven by changes in fishing regulation between the U.S. and Mexico. The California fish populations had been depressed for decades, but this was hidden by fish from Mexico.

Giant sea bass populations in Mexico have declined, but are still much healthier than researchers thought.
Meru Brito, CC BY-ND

Better data, better management

Based on my research, I believe that the giant sea bass may not qualify as a critically endangered species. My analysis of modern catch data suggests that the population of this iconic fish is likely much larger than biologists previously thought, especially in Mexico.

I am leading the next assessment for the International Union for Conservation of Nature, and now that we have accumulated better data, we can make a more informed decision that balances responsible management of the species with human needs.

I hope that our study inspires policymakers in the U.S. and Baja to start a conversation about how to manage this incredible fish in a collaborative way. But I feel our work also has larger implications. It shows how asymmetry in research and data can create significant barriers to understanding the past and present status of a species like the giant sea bass and make it harder to implement sustainable practices for the future.

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Arturo Ramírez-Valdez, Researcher, University of California San Diego

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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The World’s Longest Border

China and India’s border dispute is a slow-moving environmental disaster

Development is peaking in the high country between India and China.
Vinay Vaars/Wikimedia Commons, CC BY-SA

Ruth Gamble, La Trobe University

Chinese and Indian competition on their shared Himalayan border is more likely to create a slow-moving environmental catastrophe than a quick military or nuclear disaster.

The Himalayan plateau plays a crucial role in Asia. It generates the monsoonal rains and seasonal ice-melts that feed rivers and deliver nutrients to South, Southeast and East Asia. Almost half the world’s population and 20% of its economy depend on these rivers, and they are already threatened by climate change. China and India’s competition for their headwaters increases this threat.

Until the mid-20th century, the Himalaya’s high altitude prevented its large-scale development and conserved its environment. But after the Republic of India and the People’s Republic of China were created in the late 1940s, these two new states began competing for high ground in the western and eastern Himalayas. They fought a war over their unresolved border in 1962, and have scuffled ever since. The most recent clash was in 2017, when China built a road into Doklam, an area claimed by Bhutan and protected by India.

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Read more:
Lessons from the Doklam Pass: how little Bhutan faced down China over a border dispute

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Tensions rose again last week when China unveiled a new mine in Lhunze, near the de facto border with India’s northeastern state of Arunachal Pradesh, east of Bhutan. The mine sits on a deposit of gold, silver and other precious metals worth up to US$60 billion.

Most analysis of the Sino-Indian border dispute has focused on the potential for another war between these two nuclear-armed neighbours. The environmental impacts of their continued entrenchment are rarely mentioned, despite the fact that they are significant and growing.

The various tracts of the disputed Sino-Indian border are host to many new development projects.
Author provided

All of this development along the border is built on the world’s third-largest ice-pack or in biodiversity hotspots. The region was militarised during the 1962 war, and has since been inundated by troops, roads, airports, barracks and hospitals. These have caused deforestation, landslides, and – if a study on troop movements on other glaciers is any guide – possibly even glacial retreat.

The buildup of troops on the border has displaced local ethnic groups, and they have been encouraged to give up their land to make way for intensive farming. Animal habitats have decreased and clashes with tigers and snow leopards have increased. Population transfers and agricultural intensification have even heightened the risk that antibiotic-resistant superbugs and other toxic pollutants will seep into the world’s most diffused watershed.

During the past 20 years, first China and then India have increased this degradation by building large-scale mines and hydroelectric dams in this sensitive region. These projects have not been profitable or environmentally sound, but they have solidified state control by entrenching populations, upgrading transport networks, and integrating these fringes into national economies. The tightening of state control along the border has been further complicated by calls from the Tibetans and other ethnic groups for greater autonomy.

Many of the projects have been developed within the transnational Brahmaputra River basin. This river’s headwaters are in China, but most of its catchment is in Arunachal Pradesh, which is controlled by India but claimed by China. It then flows through Assam and Bangladesh, where it joins the Ganges River. Some 630 million people live in the Ganges-Brahmaputra River catchment.

China and India’s geopolitical resources rush threatens the safety of this entire river system. The new Lhunze mine’s position among the Brahmaputra’s headwaters is so precarious that its owner, Hua Yu Mining, was only allowed to mine there under strict environmental conditions. To its credit, Hua Yu has agreed to be a “green” miner, limiting emissions, water use and minimising “grassland disturbance”. But even if the company does not inadvertently leak acid and arsenic into the environment like other mines in Tibet, the mine is still liable to be damaged by the region’s frequent earthquakes. Any toxic leak from Lhunze will flow straight into the Brahmaputra and then into the lower Ganges.

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Read more:
China’s growing footprint on the globe threatens to trample the natural world

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On its side of the border, India has concentrated on dams rather than mines. Between 2000 and 2016, the Arunachal Pradesh government approved the construction of 153 dams, before realising that it had overextended itself.

So far only one dam is complete, and all the other projects have stalled. One of these stalled dams is on the Subansiri River, the same river from which the Lhunze mine draws water. India is racing to build these dams without community consultation or environmental studies because it sees itself as competing with China for the region’s water. China has already built four dams in the upper Brahmaputra River basin.

Indian strategists argue that they can stop China building more dams by building hydroelectric projects whose need for water will be recognised under international law. Given China’s dismissal of previous rulings by the International Court of Justice, and its recent refusal to share water-flow data with India after the Doklam incident (data that India needs to plan flood controls), this strategy seems unlikely to succeed.

Even if it does, it is hard to see how building large hydropower projects in an earthquake-probne region will ultimately help India. It won’t stop China developing the borderland, and it could cause more problems than it solves.

To keep Asia’s major rivers flowing and relatively non-toxic, both nations need to stop competing and start collaborating. Their leaders understand that neither nation would win a nuclear war. Now they need to realise that no one will benefit from destroying a shared watershed.

Ruth Gamble, David Myers Research Fellow, La Trobe University

This article was originally published on The Conversation. Read the original article.

Media Release: Australia – River Red Gum Drive

The link below is to a media release concerning the new River Red Gum Drive being established on the border of NSW and Victoria in Australia.

For more visit:
http://www.environment.nsw.gov.au/media/OEHMedia13102203.htm

Colombia: Uncontacted Tribe

The following link is to an article on an uncontacted tribe in Colombia, South America. The tribe is found in the Rio Pure National Park, near the Brazilian border.

For more visit:
http://news.mongabay.com/2012/0419-uncontacted_tribes_colombia_photos.html

Saola Found in Laos Sadly Died in captivity

Being the size that it is, it is hard to believe that Saolas are rarely seen. Not only is it rarely seen, but the Saola was only discovered in 1992. The Saola is best described as a large antelope-like creature.

The Saola lives in the mountains of the Laos and Vietnam border region.

One of these rare Saolas was captured by Laotian villagers in August 2010 and sadly died in captivity.

For more see:

http://www.wired.com/wiredscience/2010/09/rare-soala-caugh/

http://articles.cnn.com/2010-09-17/world/laos.asian.unicorn.saola_1_villagers-unicorn-laos?_s=PM:WORLD

AUSTRALIA: THE NORTH MARINE REGION

Peter Garrett, Australia’s Minister for the Environment, Heritage and the Arts, today released a report on the biodiversity, ecosystems and social and economic uses of the oceans of northern Australia. The report entitled ‘The North Marine Bioregional Profile,’ brings together and explores the available knowledge of the Arafura and eastern Timor Seas, from the Northern Territory/Western Australia border to Torres Strait, including the Gulf of Carpentaria.

The report is expected to assist the government to better understand and protect our marine environment, conserve biodiversity and determine the priorities in our marine conservation efforts. It will also assist industry to better plan and manage their activities in the region.

A Marine Bioregional Plan for the region covered in the report is expected to be handed down in 2010. In total there will be five plans covering Australia’s marine regions.

View The North Marine Bioregional Profile at:
http://www.environment.gov.au/coasts/mbp/north/index.html