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To inform, inspire and motivate the world about wildlife and why its conservation is critical to the future of humanity.

Fish like the Sound of Healthy Coral Reefs

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Using underwater speakers to broadcast recordings of healthy coral reef ecosystems encourages fish to find and settle on damaged and man-made reefs.

Lizard Island Reef, Queensland

The results of an experiment undertaken at Lizard Island, Queensland, show that playing the sounds of a healthy reef ecosystem is associated with higher rates of colonisation of man-made reefs by fish species, as compared to the rates seen at reefs where the sounds weren’t broadcast. 

The study examined thirty-three man-made coral-rubble piles designed to approximate a reef structure. Eleven reefs included a broadcast speaker. The remaining ones were used as control groups, half with a dummy speaker and half without. 

Damselfish (Pomacentrus nagasakiensis) Image from Wikipedia

Over a forty day survey period the reefs with acoustic enrichment showed the highest rates of colonisation by damselfish (a common and abundant family of reef fishes), which remained in high abundance throughout the survey. After forty days damselfish were twice as abundant at enriched reefs as compared to the control group reefs.

At the end of the survey period, more juvenile fish were present at acoustically enriched reefs. The overall number of species was higher, and the developing fish communities more diverse. 

This means that playing healthy reef sounds at a location attracted higher numbers and more varied species mixes of herbivorous, omnivorous, planktivorous, invertivorous and piscivorous fish.

The two control groups – reefs with dummy speakers and reefs without – showed no significant differences between each other for any of the survey measures. 

It seems that new reefs are not colonised equally, and the appearance and added habitat diversity provided by a speaker doesn’t improve a reef’s attractiveness to fish. 

Climate change and human-caused disturbance is triggering large-scale change to coral reefs around the world. The broad scale impact of coral bleaching events is particularly concerning to those who are tasked with managing and conserving the ecosystems.

Coral with fish by lpittman from Pixabay

Diverse fish assemblages help to maintain the overall health of coral reefs because they perform a variety of important functional processes. Having healthy fish populations gives a reef a better chance of staying healthy and recovering from damage. 

The problem is that a damaged reef sounds less appealing to young fish looking for a place to live. 

While smell is another important factor leading fish to new homes, it’s hard to efficiently replicate. Broadcasting the sounds of a healthy reef is much more practical for reef managers, and it’s a known attractant for a wide variety of juvenile fish.

It’s not known exactly how the broadcasted sounds affected the fish communities – whether they made the reefs easier to find or more attractive to settle on once the fish arrived; or a mix of both. 

Regardless of the exact mechanism, it looks like broadcast speakers might be a useful tool in bringing fish back to damaged coral reefs.

This is likely to benefit wider areas than those immediately surrounding the loudspeakers, with fish forming small-scale communities that in turn create more niches for different species to fill; increased activity (sound and smell) helping to direct more fish to the area; and natural behaviours causing the residents and their offspring to migrate away from the original settlement area as they progress through their lifecycles.

Sound as a tool for ecosystem management is only a recent development. It has been used to affect the behaviour of some birds and mammals, and fish living in various fresh and marine environments show habitat selection influenced by sound. 

Using sound to help manage coral reefs might guide new techniques for conserving various other aquatic systems where restoration projects are underway.

Joe Brennan

Starlight, Star Bright: Firefly Conservation at Home

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What do you call those insects that glow?

If you’re from the American South or surrounding regions, you probably call them lightning bugs. If you’re from the West or New England, you probably say fireflies. But there are exceptions, variations, complications, and half a dozen or so other names, including candlefly, firebob, and lamp bug. Whatever you call them, you probably remember them fondly from childhood—long June evenings spent chasing flickering, living stars.

If it seems like there aren’t as many of them as there used to be, it’s not your imagination

Introducing the Lampyridae

By any name, the little glowing insects are beetles. They are not just one species but thousands worldwide, in several different groups—the lampyrids, as they are known officially, are an entire family of beetles, meaning species of lightning bug can be as different from each other as a house cat is from a lion.

Image from Wikipedia

Most adult lampyrids glow at night in order to find mates; the color and the pattern of flashes indicate the species so that each insect can find a mate of its own kind. In one group, however, females can also mimic the flash pattern of other lightning bug species in order to attract prey (they do not eat males of their own species). Otherwise, lampyrid adults either eat pollen and nectar or do not eat at all, depending on the species. In some groups, females are wingless and signal males from the ground, while in others both sexes fly. There are also diurnal lampyrids that either don’t glow as adults or glow only weakly. These depend on pheromones, not light, to find mates.

All lampyrid larvae, regardless of species, glow (they do not flash). They live on or in the ground, where they eat slugs, snails, and worms. Despite being called “glow worms,” these young insects are not worm-like; they have strong legs.

The phrase glow worm can also apply to those females who remain flightless as adults, or to members of other glowing insect groups. In the American tropics and subtropics, the term is likely to refer to another beetle family, the phengodids. The phengodids also glow as larvae and as flightless adult females. Adult, flying males may also glow weakly. However, phengodids do not otherwise resemble fireflies and may or may not be closely related. There are other glow worms in other parts of the world, perhaps most notably a species of carnivorous, cave-dwelling fungus gnat in New Zealand.

Image by Hans Braxmeier from Pixabay

Among lampyrids (and possibly among the various unrelated glow worms as well), the light is produced in specialized organs where a chemical called luciferin is allowed to mix with oxygen to become oxyluciferin. Then oxyluciferin reacts with the enzyme, luciferase, and glows. Adult lightning bugs can flash their lights by controlling the flow of oxygen to their light organs. Larvae and some flightless females glow steadily without flashing because they cannot control the oxygen flow.

The little lamps of lampyrids may be yellow, green, blue, or even red, depending on species. The flashes may be rapid or slow, calling attention to various display-flight patterns. Some species can synchronize their flashes; there are places in the world, such as parts of southeast Asia or a few pockets in the American South, where entire riverbanks flash on and off, or where waves of light sweep across whole hillsides. As to why fireflies are so much fun to catch—if you can get close enough to one before it vanishes back into the night it will land on your open hand—I’ve long suspected that the insects must either be poisonous or taste terrible and so have no predators, but like most people, I didn’t really know much about these familiar but mysterious little creatures. Then I set to researching for this article and it turns out I was right; don’t eat fireflies.

Conservation Concerns

Lampyrids are in trouble worldwide, but it’s difficult to be sure how much trouble. There are thousands  of species, some of which may be doing alright while others may be critically endangered, and most have never been formally assessed. For most, nobody is sure that their populations are falling because nobody knows what their populations used to be. Very few people even know how to tell one lightning bug species from another. Unfortunately, lampyrids are not the only invertebrates for which such a lack of information is causing a problem; the living world is so diverse that even naming everything that’s out there is an overwhelming task, let alone figuring out which species need help.

Although in recent years some long-term monitoring of a few firefly populations has begun, the conclusion that lamprids are in trouble rests on a combination of indirect assessments—there is a large and growing number of anecdotal reports of population declines; other, better-studied insect groups are definitely declining; and many lampyrid species have characteristics well-known to be associated with vulnerability to extinction.

These vulnerabilities include:

  • Specialized diets (if their few prey species die out of an area, the larvae can’t switch to different foods)
  • Poor dispersal ability (if an area loses its fireflies, more can’t move in from a neighboring population)
  • Vulnerability to pesticides (the larvae are carnivores, so they can accumulate large doses by continually eating contaminated prey)
  •  Requires darkness (light pollution is especially bad for species that use their lights to find mates).

What You Can Do to Help

The bad news is that our lovely living lights are in trouble, but the good news is that there’s plenty you can do to help them—this is not a situation where success depends on decisions made by a few powerful people far away. It’s another opportunity for conservation literally in your own backyard. Many species of lampyrid can do very well in urban and suburban environments, provided they get a little consideration for their needs.

Basically, just leave your yard a little messy.

And if you don’t have a backyard of your own, you can still advocate for firefly-friendly conditions in your community—you’ll be helping other, less visible, species with similar needs while you’re at it, too.

  • Minimize pesticide use, and do not use broad-spectrum pesticides at all.
  • Leave some fallen leaves and undisturbed, un-tilled ground where the insects can over-winter.
  • Provide native vegetation of different heights (long grass, shrubs, wildflowers) and a source of water, both to protect and shelter the insects themselves and to shelter the slugs and snails the larvae need to eat. If the females of your local species are flightless, varied vegetation gives them good perches to display from, too.
  • Turn off unnecessary outdoor lighting—security lights can be put on motion sensors—and advocate for reduced light pollution in your community.

For more information on helping our little glowing neighbors, contact the Xerxes Society. For more information about fighting light pollution, contact the International Dark-Sky Association. For information and support on naturalistic landscaping (and a handy-dandy yard sign to let your neighbors know you’re doing this on purpose!) contact the National Wildlife Federation’s Backyard Wildlife Habitat Program. And if you have a difficult time reducing or eliminating pesticides (perhaps your homeowners’ association disagrees or you wish to change the management policies at a local park) there are organizations that can help you, including Non-Toxic Communities.

It doesn’t matter if you call them lampyrid beetles or firebobs, the important thing is to decide whether you want your nights bright with living stars.

Caroline Ailanthus

Dinokeng Big 5 Anti-Poaching Support Program

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The Dinokeng Big 5 Game Reserve, although a government initiative, receives no funding for its anti-poaching activities. This incredible swath of land is surrounded by human settlements and is thus susceptible to incidences of snaring, poisoning and poaching.

During 2020, as the Covid-19 lockdown pushed communities further into poverty, there was a sharp increase in poaching and snaring as people looked towards the reserve as a source of food. This resulted in an increased setting of snares that were intended for antelope. Unfortunately, other species can be unintentionally harmed, such as the four-year-old male lion that was caught in a snare. This lion died slowly over a period of days.

To cover such a large area, better equipment such as telemetry and communications devices are required, all of which are lacking with the skilled and brave units that protect this land are currently lacking. The Kevin Richardson Foundation has been subsidising salaries of Dinokeng staff for months during the lockdown but there is a massive need to scale up these efforts and so it has planned the Dinokeng Big 5 Anti-Poaching Unit (APU) Support Program.  

This exciting new program is structured around direct support and local community outreach. (https://kevinrichardsonfoundation.org/antipoaching/)

  • Direct support consists of continued subvention of APU team salaries, training, protective clothing, all-weather gear, number plate recognition cameras, telemetry equipment and equipment for dogs and horses used in APU operations.
  • Community Outreach communicates the benefits that the reserve brings to the local community including employment, feeding schemes and education, tourism, investment and how poaching destroys these benefits, i.e. involving the community in reducing the enticement to poach
  • A highly visible, tangible and effective way to engender community support has been proven to be through the Big 5 Schools Collective. This program is aimed at early childhood development, ages 3 – 5, and creating an early introduction to South Africa’s national wildlife treasures – the Big 5, instilling foundational awareness and care for wildlife.
    Through the Covid-19 lockdown, the Foundation partnered with the Southern Lodestar Foundation to feed hundreds of children who usually get their only meal at school. Due to school closures, there was an immediate need for feeding. Through this program, significant inroads with the community and schools of Kekena Gardens have been made. The schools will continue to be provided nutritional porridge for 5 years. By first taking care of the nutritional needs of young children, space is created to introduce a wildlife education program as well. Educational posters, play cards and storytelling teach children both the Big 5 of wildlife and the Big 5 of human values through observing these characteristics in the Big Five African mammal species.

Why this approach?

  • Education
    A large portion of South African people live on the fringes of wildlife habitat, yet never benefit from it. To decrease human-wildlife conflict in these areas and ensure the next generation views wildlife as more than just “natural resources”, it is imperative to introduce them to the wonders of wildlife at the critical early age of development.
    Furthermore, in an area where many households are child-headed or single-parent homes, there is a need for teaching core human values such as generosity, compassion, loyalty, courage, uniqueness etc.
    The Dinokeng Big 5 Anti-Poaching Support Program will supplement the Big 5 schools Collective to promote wildlife conservation education.
  • Lack of effective law enforcement
    High profile poaching for ivory, rhino horn, pangolin scales and high-value charismatic species garner most headlines and attention whilst “subsistence” poaching is often ignored and overlooked. Pursuing and prosecuting “subsistence” poachers appears to be a low priority for local law enforcement and the judiciary. The National Environmental Management: Biodiversity Act (NEMBA) provides for substantial maximum fines and criminal sanctions. But there are no compulsory minimum sentences, penalties for non-threatened species are paltry and are thus not vigorously enforced. Penalties are often based on confiscating assets and fines, but of course, these are ineffective sanctions against the poverty-stricken. https://conservationaction.co.za/wp-content/uploads/2013/11/Wildlife-Legislation-in-SS-Africa-Nov-13.pdf
    Therefore, a fundamental change in community attitudes to poaching is required and this can be achieved by demonstrating and communicating the advantages of the reserve to the local community.
  • Subsistence bushmeat hunting has been practised for millennia but increases in human populations mean that harvests are no longer sustainable. Illegal hunting and the bushmeat trade may make logical sense for communities because of a lack of opportunities to derive benefits from wildlife legally and may sustain livelihoods in the short term but the benefits are modest, largely unsustainable and come at a high long-term cost in terms of the decimation of local wildlife populations. Bushmeat is a serious but underappreciated threat. http://www.fao.org/3/bc610e/bc610e.pdf
    The Dinokeng Big 5 Anti-Poaching Support Program aims to demonstrate tangible benefits to the local community from the reserve.

How big is the challenge?

The Dinokeng APU gathers statistics to monitor the extent of poaching in the reserve. More than 1,000 snares were removed in both 2019 and 2020. Since the Covid-19 lockdown started, dog hunting incursions by poachers have increased in regularity, rhino poachers have been identified for the first time in more than one year and wood theft incidents have increased to a daily rate.
Most wildlife killed are antelope such as wildebeest (gnu), waterbuck, impala and steenbok but the snares set in Dinokeng also catch other species including zebra, porcupine, warthog and in 2020, two lions.

Does community outreach work?

In 2008, WWF-Thailand and Kuiburi National Park in southern Thailand’s Prachuap Khiri Khan Province, began an experimental project to reduce poaching by enlisting the support of surrounding communities, involving local schools and outreach events. The project sought to raise awareness, increase knowledge, shift attitudes and raise compassion for wildlife. Teachers have implemented a local curriculum focused on wildlife recovery issues, requesting local communities to reconsider hunting, eating or buying wildlife and rejecting poachers by alerting the park to poacher incursions which led to poaching decreasing and wildlife increasing. To evaluate the effects, poaching pressure and wildlife population trends were monitored. Range patrols found fewer poaching signs such as shotgun shells and hunting camps. Wildlife responded to the increased freedom from persecution. Camera traps and sign surveys indicated that distributions of gaur, sambar, wild pig and muntjac, the main prey of tigers, more than doubled.
Well engaged and mobilised local communities can be a very powerful force against poaching.

https://wwf.panda.org/wwf_news/?205811/Community-outreach-essential-to-stop-poaching-and-recover-wildlife

What can I do to help?

Community outreach programs have enjoyed success and you can help too by

Keystone Species Re-introductions: An analysis of the River Otter Beaver Trial

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Wildlife re-introduction projects are becoming more prevalent. Good monitoring goes a long way towards allying community concerns when it comes to ecologically important – but socially questioned – wildlife management.

The European beaver (Castor fiber) was once found in watercourses throughout Britain. Over-hunting led to its extinction, which – although not precisely recorded – likely occurred in the late 18th Century. 

Beaver Caster Fiber Eurasian(Image by RalfS from Pixabay)

The beaver is recognised as a keystone species – having a disproportionately large effect on its environment in relation to its own abundance. Their well-known waterway engineering creates habitats and entire ecosystems – and the prehistoric British landscape, and its riparian-dwelling plants and animals – evolved within such environments. 

Removal of the beaver and subsequent major alterations to British hydrology led to the development of a highly productive agricultural landscape – at the expense of riparian wildlife.

In 2009, the Scottish Beaver Trial was the first such enterprise to re-introduce beavers to the British landscape. Following this, several such trials have been implemented.

In February 2015, the Devon Wildlife Trust issued a licence for the River Otter Beaver Trial (ROBT) to release beavers into the wild. This followed the discovery of a wild breeding group of beavers living on the River Otter in East Devon. 

As part of a campaign supporting the retention of these wild beavers, the re-introduction project aimed to assess the impacts of beavers on the Otter catchment; its wildlife, local economy and people. Scientific assessment of these factors was hoped to provide a sound evidence base in order to determine the future of the population.

A robust monitoring programme was designed to assess the positive and negative impacts of beavers in the River Otter Catchment, and the five-year study was implemented. 

Monitoring Programme Results

With the set term ending in March 2020, the results offer future guidance on beaver re-introductions in Devon – with outcomes pertinent to the rest of the United Kingdom.  

The study has shown that the beaver population in the River Otter Catchment is increasing, and 13 separate territories were identified by 2019; stemming from the two family groups that founded the project in 2015.

The population has dispersed through the River Otter and smaller River Tale, as well as lesser tributaries – and shows that the Catchment can support a self-sustaining beaver population. 

Beaver dam (Image by Daina Krumins from Pixabay)

This population expansion has led to 28 beaver dams recorded in 2019 – predominantly in smaller tributary streams as the main stem of the Otter River is too large. The Tale experiences temporary, dynamic dams which are washed out in seasonal high flows.  

Of the 594 kilometres of watercourses within the Catchment, 1.9 kilometres (representing 0.3% of waterways) were impounded by beavers when assessed in October 2019.

This activity has of course impacted surrounding land use to some extent. Management of several spillways, culverts, agricultural land and waterways close to roads and access tracks has been required to keep water levels at acceptable levels. 

In one instance, riverside orchards were impacted by the feeding behaviour of beavers, as well as maize crops – which could be managed with minor visual disturbance to the areas (from such devices as tree guards).

Several trees were also felled over public footpaths and subsequently cleared.

As for benefits gained, beaver activity has delivered significant ecological benefit – with new wetland habitat created and managed. This in turn has benefited amphibians, wildfowl and water voles.

Fish abundance was found to be 37% higher within a beaver dam pool on the River Tale, as compared to upstream and downstream sites. Increases in minnow and lamprey populations were observed. Comparatively, the habitat and flow dynamics formed by washed-out dams created favourable habitat for juvenile trout. 

It remains unknown as to the impact of dams on migrating salmonoids in the Catchment; however trout were observed navigating past dams during high flow events. 

One village at risk of flooding saw a reduction in peak flows due to a series of dams constructed upstream, which spread water over the floodplain.

The results of the five year monitoring program show that the costs of beaver activity – while present and requiring acknowledgement and management – were outweighed by the benefits provided to ecosystems and communities. 

It’s recognised that, at a catchment scale, the benefits incurred can accrue at the same locations as the cost (in such examples as biodiversity gains due to wetland creation) but also in other locations (such as flood threat reduction downstream of dams). This is of importance as those who benefit most from a factor mightn’t be the ones bearing the cost. 

Increasing public acceptance of the beaver re-introduction project was also shown through the monitoring. This is a positive outcome showing that attitudes can and do change in regards to wildlife management – as long as information is accurately collected and demonstrated to those concerned; and appropriate management is put in place.  

Joe Brennan

The Decimation of the Global Shark Population

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Much of humanity has a love-hate relationship with sharks, a fascination and respect for their grace and power and an instinctive satisfaction when a shark is reported dead. Like a snake or a spider, the shark evokes something primal and fearful in many people. The vast majority of human contact with sharks is through a screen, a virtual world that is not actual contact at all—merely visual, imaginary. The Hollywood movie Jaws (1975) no doubt contributed to today’s disregard for their natural place in the wild kingdom—humanity’s impact on this planet has dethroned the ocean’s apex predator and the implications are far-reaching. Sharks are key in maintaining a healthy marine ecosystem; their very presence creates a “fear landscape” that molds and fine-tunes the fitness of myriad species that fall under the predator’s pyramid of influence. Even the human being, a terrestrial air-breathing mammal, is struck with fear similar to the nervous systems of the other sensing creatures who encounter the awe-inspiring shark.

Great white shark (Image on Pixabay)

Many reports indicate that the global shark population, along with many other marine species, has declined at an unprecedented rate and to a drastic extent. It is estimated that ~30% of the hundreds of shark species are threatened (vulnerable to endangerment in the near future). Reports estimate global shark stock has declined (in the last ~50 years) somewhere between 50% and as much as 99%. Many studies favor the ninety percentile estimate and few—if any—studies offer more positive data that would indicate global shark populations are healthy or even stable. There is also consensus about the leading cause of the decline, overfishing. This human act is so far-reaching in its effects that the global population numbers of many shark species has reached dangerously low levels. The iconic great hammerhead shark is listed as endangered. Sharks regardless of their endangered status continue to be intentionally plucked out of the sea via nets and hooks, ~100 million sharks are killed by humans each year.

It turns out that shark populations are not easy to study. The claim that ~90% of the world’s shark stock has vanished in the last few decades should raise suspicion. Sharks are indeed a diverse class consisting of hundreds of species (new species are actively being discovered). They are elusive for much of their life cycle; their reproductive and migratory patterns are not well understood. This is an area of study ripe for scientific exploration, a class of animals ideal for continued conservation efforts.

Challenges estimating the baseline

A major problem facing shark conservation is estimating the baseline of shark populations in the past, prior to human influence. What were their numbers in the past and where were they distributed? These details are not well known. Historic records of fishing logs, going back in some cases a couple hundred years, and modern reports from divers, as well as technical methods such as retrieved telemetry and even innovative DNA testing (measuring trace genetic fingerprints of sharks) are some of the best data used to piece together their ranges and population numbers.

The decimation of the global shark population is largely ignored and misunderstood, its relevance underestimated like so many ecological factors. In some cases, the ignorance is so great that the decline is seen simply as a triumph over a beast. Unlike cuddly koalas or even the regal but deadly tiger, sharks do not for the most part illicit compassion nor public support for their conservation.

Sharks are the apex predators of the marine environment. This “apex” means they are key, or to use another ecological term, sharks often represent the “keystone species” in a marine ecosystem, the top species in the hierarchy of natural ecological function. Their role is crucial in maintaining a healthy balanced marine environment. Keep in mind that sharks have patrolled Earth’s oceans for more than 400 million years—well before Pangea began to converge into a great supercontinent and prior to the presence of any reptile or trees on the planet. The imbalance created by weakening the apex species in an ecosystem triggers a myriad of known and unknown factors. The one thing that is apparent is that shark populations have declined and overfishing and outright intentional slaughter of sharks worldwide has dropped the global population to ~10% of what it was in the mid-1900s. That would be equivalent to the global human population of ~7.8 billion (2020) declining suddenly within a few decades to 780 million people.

Measuring the big picture trends of the current global shark population is tricky for several reasons. Namely, there are relatively few baseline estimates of what “healthy” pre-industrial shark populations actually looked like; it is unclear what their numbers were, it is unclear even how shark populations migrate and spread today. There are many mysteries sharks keep, areas of study left to explore. In the research article published in Science Advances, computational marine ecologist Francesco Ferretti from the Hopkins Marine Station, Stanford University, USA, and fellow authors, used fishery and scientific survey data (including scientific scuba diving records from 1975, incidentally the same year Hollywood’s Jaws was released) to model shark populations in the “pristine” Chagos Archipelago in the Indian Ocean, south of the Maldives. Even in this pristine setting many of the studied shark species showed a decline. From the scuba data (1975 to 2012) a marked 75% decline in overall detected sharks occurred, though some species of sharks showed an increase. The remote island atolls of Chagos represent one of the last untouched marine environments where some of the shark species appear to be thriving, a vestige of a lost world from which a balanced marine ecosystem baseline could be modelled.

There are endless possibilities open to marine ecologists seeking to understand ocean ecosystems and the role sharks play, present and past. Marine scientists acknowledge that the omission of relevant historical information (fishing quotas, dive logs, etc.) typically results in an overly optimistic conservation plan, resulting in population recovery targets being set too low compared to the reality of their thriving numbers in the not so distant, but undocumented, past. If shark populations were already declining by 1975, to goal back to that baseline is to accept an already disrupted equilibrium. Shark decimation seems to be yet another example of how humans have drastically altered the planet.

Heather Sickels

5 March 2020

Mission

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Our mission is to inform, inspire and motivate the world about wildlife and why its conservation is critical to the future of humanity.

Our vision is to build a community of wildlife and conservation supporters.

We’ll do this through informative articles, making scientific articles easier to read, for those of us without a science degree. Education about wildlife conservation, how this benefits us, what we as individuals can do, proactively supporting selected projects and showcasing conservation “rock stars”.