EOFY is a good time to check gaming laptop deals, even if the laptop isn’t going to be used for work. Gaming laptops can be quite expensive, so a legitimate discount can make a bigger difference than it does on a basic everyday laptop.

That said, a gaming laptop can also be a powerful workstation if your work does need extra grunt. A fast CPU, dedicated GPU and plenty of RAM can help with video editing, 3D work, coding, running AI tools, creative apps or just keeping a lot of browser tabs and programs open at once.

It’s also worth checking our main EOFY laptop deals hub even after June 30, because in previous years we’ve seen some great laptop deals hang around or pop up in early July as retailers clear leftover stock.

For gaming laptops, we have deals from lower-cost RTX 5060 machines with generous RAM, through to much more expensive RTX 5090 desktop replacements.

The Acer Nitro V 16S is a good option for a buyer who wants current-gen gaming performance without paying big money. You still get an RTX 5060, 32GB RAM, a 1TB SSD and a 180Hz display for AU$1,777, which is a lot of hardware for the price.

The RTX 5060 is a lower-end current-gen GPU, but that’s still a good fit for 1080p or 1200p gaming, especially if you’re happy to use DLSS or turn down a few settings in the most demanding games. With RAM prices rising, 32GB of RAM is harder to take for granted at this price, so it’s good to see Acer include it rather than cutting back to 16GB.

The Lenovo Legion Pro 7i is at the other end of the scale. Our Lenovo Legion Pro 7i review described it as “perfect for a desktop replacement, just okay as a portable”, and that’s exactly how I’d frame this deal.

You’re not buying it because it’s cheap or easy to carry everywhere. You’re buying it because you want a very powerful 16-inch gaming laptop with an RTX 5090, 32GB RAM, a 1TB SSD and a 240Hz OLED screen.

Our review gave the Legion Pro 7i 4 stars and called out its excellent gaming performance, gorgeous OLED screen and useful port selection. That makes it a good fit if you want one machine for demanding games, an external monitor setup and heavier work like editing, rendering or development.

The big caveat is battery life, which our review said “is not great”, but that’s the trade-off with this kind of desktop-replacement gaming laptop.

If neither of these gaming laptop deals is quite right, our main EOFY laptop deals hub has more options across cheaper Windows laptops, MacBooks, 2-in-1s and higher-end gaming machines.

from the moral-panic-creeping-further-and-further dept

Several U.S. states are pushing to ban young people from social media entirely. This marks the latest wave of censorship bills masquerading as “children’s online safety” measures, with states like Massachusetts, Idaho, Minnesota, North Carolina, South Carolina, Illinois, and EFF’s home state of California leading the charge.

Just a few years ago, lawmakers supporting age-gating laws insisted their efforts were narrowly targeted at limiting young people’s access to adult content. At the time, we warned that they would not stop there: once the government established the authority and built the infrastructure to collect and “verify” massive troves of user data, it would inevitably sweep broader and broader categories of lawful speech into this mass surveillance and censorship system. 

Unfortunately, our predictions came true. As legislators across the country advance proposals that would block all young people from accessing the “modern public square,” the Overton window has shifted dramatically towards mass censorship—and the speed of this shift should concern all of us. 

This primer breaks down this dangerous wave of social media bans: how they work (and why they don’t), who they harm, and how we can fight back. 

How to Spot a Social Media Ban

The details of these bills vary from state to state. Some (like California’s AB 1709) are a flat-out social media ban for all young people under a certain age, while other states (like South Carolina and Minnesota) allow access to young users who hand over even more data to show verifiable parental consent. Many bills regulate certain social media features, too, including by setting default privacy settings, time limits, or notification preferences for all accounts that fail the age-gate.

As for the age-gating mechanism itself, most proposals fall into two broad categories: age verification bills and behavioral age estimation bills. 

Age Verification Bills require online services to collect highly sensitive data, including government ID and biometric information, from all users before either restricting or allowing them access. 

For example, take California’s social media ban (AB 1709). Starting in January 2027, operating systems will be required to collect enough information from users to sort them into age groups, or “brackets.” Under AB 1709, social media apps would then use that age bracket information to completely block anyone under 16, while supposedly letting everyone else through. By contrast, Florida’s law (HB 3) takes a more aggressive route by forcing platforms to verify users’ identities directly, usually by contracting with private third-party companies to perform verification services.

Behavioral Age Estimation Bills, on the other hand, are a more recent innovation of states like Minnesota (HF 1438) and South Carolina (H 4591). These bills require platforms to estimate the ages of users based largely on data that they already collect, including self-attested age, behavioral information, and account history and activity. In practice, these bills enable tech companies to use algorithms and/or AI to analyze our online behavior and estimate age based on that. 

Proponents of behavioral age estimation bills claim that their proposals avoid the massive security risks that come with mandatory age verification bills. However, much of the data that social media platforms collect from us “in the ordinary course of operation” is collected in order to serve us targeted behavioral ads. If we force platforms to use this imperfect data to make more important judgments about who can access their services, we risk entrenching those insidious data collection practices. Surely we don’t want to give social media companies more reasons to justify and sustain their reliance on this exploitative business model.

If you want to dig into the nuance here, our terminology guide sheds more light on the technical differences between age verification and age estimation bills. 

Overall, it’s a lose-lose scenario: either platforms collect new forms of our most sensitive and immutable data, or they unleash their AI and algorithms on our existing behavioral data to make creepy guesses about who we are and what we deserve to see. No matter which age-gating method your state chooses to execute its social media ban, there will be lots of error at the margins—and lots of users who will be blocked or chilled from access to lawful online speech.

Why Social Media Bans Are So Dangerous

Social media bans are unconstitutional, discriminatory, and deeply misguided. They reinforce existing structures of oppression, and they are broadly unsupported by young people, whose voices are conspicuously absent from this conversation. They undermine parental decision-making and replace tailored family-level solutions with a one-size-fits-all band-aid. And, in the places we have seen social media bans go into effect, early reports show that they don’t even work. 

For example, in Australia, where a social media ban has been in effect since late 2025, a majority of young people can still access social media, those who can’t have lost their access to the news, and crisis helplines are reporting skyrocketing numbers of calls from youth left stranded without online community or resources.

We could go on and on about all of the inherent harms here, but we’ll try to keep this short as we walk through some of the major issues.

1. Security Risks and Privacy Harms

In order to ban some users, social media platforms first must confirm the ages of all users, regardless of age. Bans thus incentivize companies to force users of all ages to hand over government IDs, face scans, and other sensitive information. When parental consent is required, companies must collect even more verification data and often create explicit links between child and parent accounts—further destroying users’ anonymity. 

Both of these databases create massive data “honeypots” that invite identity theft and permanent surveillance. We’ve already seen repeated data breaches involving age- and identity-verification services. Yet these laws would force both adults and the youth they claim to protect to feed their most sensitive data into this growing surveillance ecosystem. 

If we don’t trust tech companies with our private information now, we shouldn’t pass laws that force us to give them even more of it. 

2. Disproportionate Harm to Vulnerable Communities

Age-verification technology is deeply flawed and prone to discrimination. These systems frequently misidentify or lock out people of color, people with disabilities, and trans or gender-nonconforming individuals whose IDs may not match their appearance. 

Where these bills require parental consent, they impose disproportionate access barriers on low-income, non-traditional, and immigrant families. These sorts of families are more likely to share a single family device or have strong reasons to not want the government to track family associations and ID documents. 

Beyond the technical failures, these bans cut off a vital lifeline. For LGBTQ+ youth, foster kids, and those stuck in unsupportive home environments, social media is often the only place to find community, explore their identity, or access life-saving resources. Forcibly removing young people isolates those who need connection the most, while creating massive new barriers for adults. 

You can read a breakdown of the diverse groups vulnerable to these laws here. 

3. Based on Shoddy Science

The current legislative push to ban young people from social media relies heavily on the idea that the “great rewiring” of the adolescent brain is a proven fact. This simply isn’t true.

Social science indicates that moderate internet use is a net positive for teens’ development, and negative outcomes are usually due to either lack of access or excessive use. For LGBTQ+ and marginalized youth in particular, social media offers an essential space to access support they might lack offline. By forcing youth into digital isolation, these bans cut off vital access to political news, community, and health resources. They also completely ignore the calls of young people themselves who favor digital literacy and education over restrictive government control.

Instead of cutting off these lifelines, we should support measures that arm all youth (and the adults in their lives) with the knowledge they need to navigate online spaces safely.

4. Reckless Free Speech Violations for Users of All Ages

No matter your age, the First Amendment protects your right to speak and access information. 

Blanket social media bans immensely and unconstitutionally chill all users’ exercise of this right. They cut off young people’s access to lawful speech, or ruin their privacy in the home by mandating parental consent and sometimes even parental access to their account activities and settings. They force all users (adults and young people alike) to hand private information over to tech companies before speaking or accessing information on social media platforms, imposing annoying obstacles on lawful online expression and wrongfully blocking some adults outright. 

Critically, these bans destroy our right to online anonymity—a cornerstone of our right to free expression that protects whistleblowers, journalists, activists, immigrants, and everyone who has ever used a private browser or account to ask the internet an embarrassing question.

How to Fight Back

Social media bans weaponize parents’ concerns about children’s safety to justify unprecedented levels of surveillance and censorship. In the process, these laws deny young people their rights, threaten online anonymity for everyone, expose our sensitive personal data to breach and abuse, and replace parental decision-making with state authority. This is a battle over the future of the open, private, and free internet, and we must act now to protect it.

Here’s how you can help us fight back: Talk to your community (including young people!) about what’s at stake. If you’re a parent, lean on open conversations and platforms’ existing tools to tailor your child’s experiences instead of handing that power over to the government. And no matter where you live, contact your government representatives and tell them clearly that social media bans are not the answer to kids’ online safety.

Republished from the EFF’s Deeplinks blog.

Filed Under: age estimation, age verification, california, free speech, idaho, illinois, massachusetts, minnesota, moral panic, north carolina, social media, social media ban, south carolina

Looking for a deal on a Yeti cooler for your July 4th celebrations? I’ve got you covered. As the former editor of an outdoor adventure website, I know exactly where to look to find the best offers on Yeti gear, and I have uncovered some great deals that will arrive in time for the big day.

Amazon has some great offers, particularly on soft coolers like the Hopper Flip 8 and 12, both of which are ideal for cans or lunches. There are also big discounts on the roomier Yeti M Series, including backpack-style coolers that make carrying your food and drinks a breeze.

Want a hard cooler? Take a look at Yeti Rescues, where you can find heaps of like-new coolers approved by the company itself, and with big price cuts. It’s a smart way to get a top-quality cooler for a lot less than list price. I’ve tested outdoor gear for years, and these price cuts are rare, so grab them while you can.

Yeti’s online store often holds seasonal sales and special deals on selected colors and product lines. Here are today’s best offers.

Yeti Rescues deals

Can’t see the cooler you want in the Black Friday sale? Take a look at Yeti Rescues — an official Yeti program that takes coolers and other equipment that’s not brand spanking new (products that have been returned, for example, or that Yeti has used for demos or displays), inspects them, cleans them, and sells them at a bargain price.

More Yeti deals

Amazon and Yeti Rescues aren’t your only options when you’re shopping for a cheap Yeti cooler. Dick’s Sporting Goods has a decent selection of offers as well. I’ve rounded up a handful of the best below, but you can also check out the full sale yourself.

Follow TechRadar on Google News and add us as a preferred source to get our expert news, reviews, and opinion in your feeds.

Google announced on Monday that the Gemini app is now offering its personalized Nano Banana-powered image generation feature to a broader audience. Starting today, all eligible users in the U.S. can access the feature for free, a service that was previously only available to Plus, Pro, and Ultra subscribers.

Google initially announced that Gemini’s Personal Intelligence feature would get Nano Banana-powered image generation back in April, allowing users to create images that reflect their unique interests. This means that images can be generated based on Gemini’s understanding of your likes and preferences without you having to specify them in your prompt. Gemini utilizes data from your Google account connections — such as Gmail, Google Photos, YouTube, and Search — to achieve this. 

For example, instead of saying, “Create an illustration of me and my favorite things, such as coffee and baking,” you can simply request, “Create an illustration of me and my favorite things.”

Gemini can also pull actual images of you from Google Photos, so you don’t need to manually upload photos. 

Google initially rolled out the Personal Intelligence feature earlier this year, making it widely available to all U.S. users in March. The company recently expanded this functionality to users in India and Japan. 

Personal Intelligence is an opt-in feature, allowing you to decide which apps Gemini can access. Once enabled, it is set as the default for every prompt, but you can disable it using a new toggle in the Tools menu.

Additionally, last month, Google announced several upcoming updates for the Gemini app, including a new “Daily Brief” feature, a revamped interface, access to AI video model Gemini Omni, and a personal AI agent named Gemini Spark.

Notably, Google’s AI chatbot Gemini surpassed 750 million monthly active users (MAUs) earlier this year, reinforcing its position as a major player in the AI space.

Some of Apple’s corporate secrets aren’t so secret any more.

Compare Our Top Picks

Honorable Mentions

Photograph: Julia Forbes

We tested many mattresses last year and have hit the ground running in 2026. That said, here are a few options we enjoyed and considered but ultimately didn’t make the starter team.

Leesa Original Hybrid Mattress for $1,499: If you don’t mind the bouncy feel generated by the innerspring core, this is a well-engineered mattress that will appeal to most people—it’s not too firm but not too soft, with excellent edge support and an 11-inch height that won’t feel too tall or too low on your bed frame. It’s got a top layer of memory foam, but because of the Original’s sturdy hybrid construction, which incorporates 789 individual pocketed coils, you won’t get the dips or mashed-down spots over time that you might with a foam-only mattress, which can be a real problem for couples. You also can’t beat Leesa’s limited lifetime warranty. The only note is that while Leesa quantifies the Original’s only firmness level as a “medium-firm,” it is definitely on the softer side, so if you’re looking for a true medium-firm, you may want to consider a “firm” from another model. I also tested this with the optional Cooling Quilt Top, which I recommend if you sleep hot, as it was cool to the touch and helped reduce heat absorption overnight. —Kat Merck. $1,050 to $1,664

The Purple Mattress for $1,599: Purple’s signature squishy GelFlex grid is, like Tempur-Pedic’s Tempur-material, divisive: You are either a rabid super-fan or consider it the worst mattress you’ve ever slept on in your life. My household consists of the former. Along with your mattress, Purple sends a little rectangle of the material so you can see exactly what it is: A rubbery polymer grid that crumples to relieve pressure in areas where you need it, like your hips and shoulders. Because each square of the grid is open, it allows for plenty of airflow, and because the gel is squishy, it still absorbs motion transfer just like memory foam would. If you love that soft memory foam feel but hate the heat absorption, you will probably love Purple. And especially this model, as it best showcases the GelFlex grid without any additional foam layers to get in the way. The only problem I had with this mattress was its height: It’s around 9 inches, so if you have a low-profile bed frame and are used to a thicker mattress, it will sit quite low. I didn’t expect 2 or so inches to make a dramatic difference, but it did. Also, the GelFlex grid makes this mattress extremely heavy (make sure it’s exactly where you need it before cutting the vacuum seal), so placing a box spring or anything else underneath to lift the height will void the warranty. —Kat Merck. $1,099 to $2,598

Thuma Luxury Hybrid Mattress for $1,795: Thuma’s hybrid mattress is interesting because it blends together a smorgasbord of mattress materials: a Tencel cover, organic wool, memory foam, organic latex, and recycled-steel coils. The same rubberwood trees are used for Thuma’s popular Classic Bed frame, and for the Dunlop latex in this mattress. Of the three firmness levels offered—plush, medium, and firm—the medium was yielding some pretty strong support. The sleep trial is a bit unclear, as you only get 100 nights of coverage with your first Thuma purchase. So if you’ve already used it on a different Thuma product, like the frame, you may be out of luck here. —Julia Forbes. $1,295 to $1,995

Puffy Cloud for $1,049: This enhanced all-foam mattress offers profound pressure relief without feeling too soft, despite the name “Cloud” being in its name. The Puffy Cloud has a thinner profile and would most likely be too soft for bigger bodies. However, for lightweight and average builds, it really comes through to support the lower back and hug around pressure points. The thinness also didn’t compromise its motion isolation, which meant little to no shaking when my dogs jumped in and out of bed.—Julia Forbes. $449 to $1,298

The Saatva Contour5 for $3,049: The Contour5 is a newer offering from Saatva, replacing the popular Loom & Leaf in the company’s lineup. Like other Saatva mattresses, but unlike most others on this list, it is not roll-packed and comes delivered on a moving truck. The Contour5 has two firmness options and updated cooling tech that uses airflow channels in its gel foam layer, which is thinner than its predecessor, meaning it retains less heat. In my two weeks of testing, I found the Contour 5 was very good at remaining cool through summer nights, which is extra impressive given that it uses very dense 5-pound-weight memory foam. The Contour5 is soft enough for side sleeping without feeling like a saggy hammock and has excellent build quality, which is impressive for an all-foam mattress without springs. I prefer a hybrid with microcoils, but Saatva is popular for a reason, and as all-foam mattresses go, it has a true luxury feel. —Martin Cizmar. $1,899 to $3,649

The Big Fig Classic for $1,999: The Big Fig is designed for larger body frames. Being a bit overweight myself, I was eager to see how well this mattress, which is advertised as comfortably handling 550 pounds per sleeper, performed. It is a well-built mattress with an effective gel cooling layer; however, the aggressive edge support created a hammock-like feel despite the sturdy springs and three layers of high-density foam in the middle of the mattress. This was true both on my back and on my side. Others may appreciate the effect of sinking a bit into the center of the bed more than I do. —Martin Cizmar. $1,499 to $2,399

The Boring Hybrid Mattress for $799: Boring Mattress is a new company founded by two alums from Tuft & Needle. Simplicity is the company’s selling point. There is just one option: the Boring Hybrid Mattress. (You are allowed to pick a size.) This 10-inch hybrid has four layers of both foam and springs. I’m very sensitive to joint pain, and certain beds tend to make it worse, which is why pressure relief is super important for me. Having slept on a variety of different mattresses throughout the years, I was doubtful that this one would work. But I’ve slept on the hybrid mattress for months now and have yet to feel any pain at all. It strikes an excellent balance between firmness and support that my very particular self hasn’t been able to find with other options on the market. It’s worth noting, however, that its layers come equipped with an open-cell design that’s designed to move heat from your body while sleeping. I’m usually cold, so this feature isn’t that important to me. But on nights when I’ve cranked the heat up in my room and woken up sweating a bit, I can’t say it worked all that well for me. This isn’t a deal breaker, but I wouldn’t buy it solely for that. —Brenda Stolyar. $599 to $999

Casper The One for $899: Casper was a leader in the first wave of bed-in-a-box makers in 2014. The company has changed ownership and design a few times over the past decade but last year’s launch of The One finds the company keeping pace with competitors. This is an all-foam mattress that stands 11 inches tall. Because it’s all foam, it’s on the light side, with a queen weighing an easily movable 66 pounds. One of the main issues with all-foam beds is that they get too hot, but Casper’s The One uses an open-cell foam layer called Breathe Flex Foam on the top, which makes it both pleasantly squishy and breathable. Two more layers of foam add up to a medium-firm feel, with the middle layer designed to cradle your hips, and the base layer designed to provide support. —Martin Cizmar. $749 to $1,698

The Winkbed for $1,799: WIRED reviewer Julian Chokkattu slept on the luxury firm version of the WinkBed for almost two years and he was quite happy in that time. His favorite perk? The edge support is fantastic, so his partner never wakes when he slips into bed late at night. The plush pillowtop also adds a luxe, hotel-like feel to a relatively firm bed. —Martin Cizmar. $1,427 to $2,856

Silk and Snow S&S Organic for $950: I wouldn’t expect this to feel silky-soft, but the latex is supportive for sleep. I love how responsive (read: bouncy) this bed is, especially as someone who tosses and turns often. It’s able to move with me so I never feel unsupported, or overheated for that matter. Latex and coils are breathable, as are the organic cotton cover and wool fire barrier. —Julia Forbes. $800 to $1,300

Nest Bedding Quail for $1,299: When it comes to all-foam mattresses from classic bed-in-a-box brands, I prefer the Casper above, but the Quail by Nest is a nice option if you want an all-foam bed that’s a little firmer and you’re willing to pay a little more. My biggest issue with the Nest was that despite its claimed cooling system—the foam is infused with minerals and designed with an airflow layer—I did sleep a little hot on it during my week of testing. —Martin Cizmar. $849 to $1,499

Courtesy of Helix

Helix Sunset Elite for $3,095: Our top pick, Helix, also has an Elite collection that consists of seven mattresses along a spectrum of softness. At 15 inches high, the Sunset Elite is “the tallest mattress on the internet,” and comes shipped in two separate boxes, each heavy enough to max out FedEx requirements. The firmness is dictated by the foam density of the upper layer, which zips into a larger support system. This makes the mattress adjustable if you end up regretting your order. The bottom section has a separate layer of microcoils. I spent a month sleeping on the softest model from the Elite line, dubbed the Sunset, and appreciated the deep cradling effect. Helix offers a 100-day trial period on all of its mattresses. —Martin Cizmar. $2,871 to $4,871

Wayfair Sleep 14-Inch Plush Cooling Gel Hybrid Mattress for $324: This plush mattress has a top layer of cooling gel that conforms to your body for comfort and has classic pocket coils below for structure and support, with layers of memory foams with varying thickness surrounding the coils for extra support (the coils and memory foam mixture helps with low motion transfer, too). The top knit cover and sides help with breathability and the overall cooling effect. The mattress is also compatible with an adjustable bed base, has solid edge support, is CertiPUR-US and Oeko-Tex Certified (ensuring no harmful toxins), and has a 10-year warranty. This bed is super comfy if you like a more plush mattress. —Molly Higgins. $555 to $1,014

Mattresses to Avoid

Not every mattress we test can be a winner, which is why we test in the first place. Here are a few that did not make the cut according to our standards.

Birch Elite Hybrid for $2,619: This is the newest model from Birch, and frankly, you would be just fine sticking with the Birch Natural or Birch Luxe Natural instead. The Birch Elite Hybrid was incredibly top-heavy and incredibly difficult to move, given the floppiness and weight of its numerous latex and coil layers. The top layers slid around, creating a lumpy surface, and the new “CoolForce” layer was completely undetectable. —Julia Forbes. $2,499 to $4,499

Brooklyn Bedding Spartan for $1,499: This mattress is designed for “athletic recovery,” and as a former collegiate athlete, I was excited to try it. I had opted for medium firmness over the soft and firm options, but upon receiving it, I had to double-check that I hadn’t gotten the soft option by accident. The medium cratered around me, leaving me with unhappy pressure points. The lack of overall support didn’t help me recover from soreness, so I couldn’t tell you whether the Far Infrared Ray recovery tech in the cover helped at all. —Julia Forbes $1,099 to $2,399

Sleep Number Climate360 Smart Bed for $8,712: This bed can be temperature-controlled, which is amazing. The adjustable base means you can be comfortable when watching TV, reading, or sleeping. Unfortunately, the price tag has too many digits, and sleep experts recommend avoiding electronic usage before bed—advice the Sleep IQ app defies. Did we mention it costs as much as a used Buick and the weight is not far behind? —Martin Cizmar. $10,249 to $14,499

Tempur-Pedic Tempur-Adapt for $2,199: Tempur-Pedic is one of the country’s best-known and loved mattress brands, but two separate WIRED reviewers (Martin Cizmar and Nena Farrell) have both disliked different mattresses from the company over the past two years. Nena found the Tempur-Adapt totally lacking in support, and felt like she was sinking into a void when she lay on it. Her spine and muscles both ached after sleeping on it so she gave it to her sister who also hated it, describing it as like sleeping on a leaky air mattress. —Martin Cizmar. $1,699 to $3,398

Amazon Basics mattress for $279 (Full): This one is made of cheap foam that isn’t dense enough, causing too much sinkage. —Martin Cizmar. $189 to $386

Parachute Eco Comfort Mattress for $2,650: This mattress just doesn’t live up to its extravagant price. The model we tested didn’t have enough proper padding above its coils. —Martin Cizmar. $1,550 to $2,850

Power up with unlimited access to WIRED. Get best-in-class reporting and exclusive subscriber content that’s too important to ignore. Subscribe Today.

Catalina A Musrri of the University of Sydney and Georgina Wood of Flinders University discuss the significance of underwater seaweed forests and how to preserve them.

A version of this article was originally published by The Conversation (CC BY-ND 4.0)

Australia’s Great Southern Reef is built not by coral but by seaweed. The seaweed forests on these rocky reefs stretch more than 8,000km around southern Australia.

Amid the swaying fronds live seadragons, rock lobsters, giant cuttlefish and southern blue devils. The reef is home to more than 1,500 seaweed species and contributes billions to the economy each year.

But these remarkable cold water forests face a worsening threat. The ocean is getting steadily warmer, pushing seaweed species outside their survival zone. Much of this damage is done by sudden marine heatwaves, where temperatures spike and remain high for some time. Heatwaves have driven the decline of seaweed forests across the country.

To protect these underwater forests, we need to preserve their genetic diversity. We led the first attempt to cryopreserve (freezing and storing reproductive material at ultra-low temperatures) a key Australian seaweed, crayweed, and found the idea shows promise, though the techniques need to be perfected.

Why does seaweed matter?

Most of us encounter seaweed as a slightly stinky mass spotted when walking along a beach. But underwater, these large algae (not plants) form beautiful forests swaying in the current – some as tall as 30 metres.

Seaweed forests are among the most productive ecosystems on Earth. Like forests on land, they provide habitat, shelter and food for many creatures. They underpin valuable fisheries such as lobster and abalone.

When local populations are wiped out, they take something important with them – genetic diversity. Species with high genetic diversity can better adapt to change. Some populations will be able to tolerate heat better, for instance. But if these populations disappear, their unique genes go with them.

In 2011, an extreme marine heatwave in western Australia led to two common seaweed species losing an estimated 30pc to 65pc of their genetic diversity. These losses may mean poorer outcomes in response to intensifying threats.

Consider the crayweed

Golden-brown crayweed (Phyllospora comosa) once formed extensive underwater forests along Sydney’s coastline. Many of these disappeared in the 1980s, likely due to sewage pollution. But crayweed didn’t return even after pollution levels fell.

Over the past 14 years, scientists and divers have replanted this species around Sydney through Operation Crayweed. Their work has led to the return of self-sustaining populations, including Australia’s first named seaweed forest – Yanggaa forest at Coogee Beach.

But restoration may not be enough in a rapidly warming ocean. Our research shows separate crayweed populations harbour unique genetic diversity – and some individuals appear better equipped to tolerate heat. It may make sense to plant germlings (baby seaweed) from these individuals in vulnerable populations to boost their chances of survival.

Of seed banks, biobanks and cryopreservation

For decades, thousands of land-based plant species have had their genetic diversity preserved through seed banks. The seeds stored are sleeping but still alive. If planted in the right conditions, they will grow.

Some kelp species can also be kept alive in biobanks – not as seeds, but in a microscopic form (gametophytes) able to be kept alive in laboratories for years. Current kelp collections support research, aquaculture and restoration programmes around the world, including in Australia.

These banks are important. But they won’t be enough. The majority of seaweed species dominating the Great Southern Reef are known as fucoids. Unlike true kelps, fucoids don’t have this microscopic life stage; they release sperm and eggs directly into seawater that fertilise and form germlings. This makes species such as crayweed, bull kelp (Durvillaea potatorum), Cystophora sp and Scytothalia dorycarpa more challenging to conserve.

It is possible to bank species which rely on sexual reproduction, such as humans, cows, corals and fucoids. Assisted reproduction methods such as IVF rely on cryopreservation: storing reproductive material, tissue or early life stages at ultra-low temperatures (around –196°C) so it remains viable for future use.

Our recent research tested whether frozen crayweed sperm and germlings were viable after being thawed. We found the sperm did well, but the germlings did not (for now). Our ultimate goal is to develop proven methods able to work across a broader range of Australian seaweed species.

Preserving the genetic diversity of seaweed species would mean these genes can be drawn on to bring them back. This buys valuable time and keeps the door open for new methods such as assisted gene flow, where individuals from better-adapted populations are used to help vulnerable ones cope with warmer conditions.

Time for seaweed biobanks?

Australia already has an impressive algal culture collection and is a global leader in coral cryobanking.

Even so, it will take real work to develop methods of preserving the forest-forming seaweed species that rely on sexual reproduction. We need to learn which populations contain unique or threatened genetic diversity, understand which are most vulnerable to climate change, and improve freezing and recovery techniques.

Choosing which species and populations should be done alongside indigenous custodians, governments, conservation organisations and local communities.

Cryobanking doesn’t solve climate change or replace the need to protect habitat. It’s an insurance policy for biodiversity. Much has already been lost. Preserving the remaining genetic diversity of our seaweed forests may well be critical to the survival of the Great Southern Reef.

By Catalina A Musrri and Georgina Wood

Catalina A Musrri of the University of Sydney recently completed her PhD in seaweed forest restoration in the context of climate change. She is interested in the impacts of climate change and other anthropogenic activities, such as pollution and overfishing, on coastal habitats.

Georgina Wood is an early career Australian Research Council fellow at Flinders University and adjunct research fellow at the University of Western Australia whose research focuses on repairing nature in a changing climate, particularly temperate kelp forest ecosystems.

Don’t miss out on the knowledge you need to succeed. Sign up for the Daily Brief, Silicon Republic’s digest of need-to-know sci-tech news.