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“Stephanie, I’d like you to meet Dr. Tim Drake. Dr. Drake, this is Stephanie, the head of our marine mammal training.”

Tim pasted a smile on his face and shook her hand. How these people had managed to get their hands on a mer without a specialist on the team, he had no idea, but he was there now.

“Nice to meet you, Stephanie, call me Tim.”

“Hi, Tim, I’m glad you could come.” She gave him a polite smile, but the stress lines belied the pressure she’d been under. “I admit this is outside of my field, but I’ve been working with Big Red for almost as long as he’s been here, so I’ll help as much as I can.”

“I really appreciate that.” He turned back to Roman, the curator. “If you could show me the mer’s file, I’ll go ahead and get started.”

He and Stephanie ended up in a small conference room with the document spread out on the table in front of them.

“So what’s all going on? The posting was a bit vague, but the mer isn’t eating?” Tim flipped to the next page, trying to make sense of it. He’d never seen a file put together in such a disorganized fashion, especially since aquariums with mers were under such heavy scrutiny. 

“Yeah. We entered Big Red into a breeding program last year, and found a mate a few months ago. Before then, he was really cooperative. Easy to work with, although I always felt like I wasn’t doing enough. I’m used to dolphins, you know?” She heaved a sigh, twisting her fingers together. “But ever since the breeding three months ago, he’s been totally different. At first he just stopped responding to us. Wouldn't answer any of our signals, wouldn't come to the surface, let alone the landing rock, and the only way we could keep feeding him was to weigh it down and drop it to the bottom for him to pick up. But we had to sedate him last week to get an ultrasound, and that made it so much worse. He hasn't eaten anything we dropped in, just stays buried in the sand most of the time, and goes practically feral if anyone gets in the water. He sent one of the divers to the hospital after the ultrasound.”

Tim nodded along, filing the information away and mentally marking Big Red as ‘he.’ All mers were intersex, but if Stephanie had been working with the mer for years, it’d be easier to just adapt to her terms. “It’s pretty normal for mers to get territorial when brooding. What concerns me is that he hasn’t built a nest. He just buried himself in sand? Who are his dam and sire?” He couldn’t find the information anywhere, which was unusual. If one of Big Red’s parents had similar behavioral issues, that could be a factor, but Tim was beginning to wonder if Big Red had simply been removed from his pod too young.

“Oh, we don’t know. Big Red was brought in as a rescue when he was really young. He was all torn up after a boating accident, and by the time he’d healed enough to be released by the rehab facility, they couldn’t find his pod and he’d adjusted to humans too much. The rescue center closed a little while after Red came into our care, so all we really know is that the accident happened about fifty miles east of Gotham Bay.”

The missing puzzle pieces fell into place quickly, making such a horrifying picture that Tim dropped the paper he was holding and collapsed back in his chair. 

Stephanie took one look at his face and paled at what she saw. “What? What is it? What’s wrong?”

Tim buried his face in his hands. “You have a wild mer, who’s not an imprint,” he glanced up, hoping she’d correct him, but when she didn’t he was forced to continue, “and you put him in a breeding program.” He sucked in a breath, stomach churning. “Who was the mate? What’s their history?” 

“Um,” Stephanie shuffled through the papers, hands shaking a little as she searched for the correct one. “One of the older mers from the Pakistani National Zoo. Demon? They’d had a lot of success with him in the past, and his dam was wild also, so the breeding program leader thought it was a good match.”

“Fuck.” Tim’s face screwed up in pain. “Okay, so, that’s not good. I’m going to have to talk with your curator and the person in charge of the breeding program, because it is unacceptable how little research they did, and frankly I’m tempted to contact APHIS about an Animal Welfare Act violation. Wild mers are protected, and there’s a reason it’s illegal to put them with mers born in captivity. They have complex social dynamics, and their courtship periods can last for years because they usually mate for life. 

“Mers born in captivity lose those instincts quickly, sometimes in a single generation, and become almost feral when interacting with non-familial mers. They’re more violent towards others of their own kind, and more likely to cause serious, permanent damage when mating. Wild mers scar each other, captive mers kill each other.” 

He let the seriousness of what he was implying sink in, then continued. “These guys are smart, smarter than orcas, smarter than chimps, and most of the current research and petitions are working on halting all breeding programs, because the more we learn, the more we’re realizing that they could very well be at human levels of intelligence. If Big Red was bred by a captive-born mer, that's roughly the equivalent of throwing a feral cat at a rabid dog. Both are dangerous, but only one of them has a chance of winning.”

“Oh god.” Stephanie pressed a hand over her mouth, and she looked about ready to cry.

“It’s not your fault,” he assured her, although she had definitely contributed. “The curators should have done their research, and the breeding program director definitely should have known better. This isn’t your field, and they threw you in without the information you needed. That said, I’m going to be changing some things.” A lot of things. “Can I see the tank?”

Stephanie led him through the aquarium, bypassing all the little areas meant to break up the flow of visitors until they arrived at the right tank.

He would give them credit in that the tank was the right size for a single mer. That was all the credit they would be getting, however. It was clear that Stephanie had done some research on mer enrichment, given the large rock formation with lots of caves and tunnels, but as far as he could see there wasn’t a single living thing in the tank as far as flora went. As it was, he really couldn’t see a single living thing period, because wherever Big Red was hiding, it was not visible from the main viewing area.

“Where has he been hiding?” he asked Stephanie.

“Over here.” She led him to a far corner, then pointed back deeper in the tank where he could just barely see a small rise in the sand against the wall. “It took us forever to find him, but that’s the only corner in the tank where neither wall is glass. We tried setting up an underwater camera so we could watch him discreetly, but he destroyed it pretty quickly.”

"Okay." Tim nodded, a plan coming together in his head to fill in all the things that were missing. Big Red hadn't built a nest because there was nothing to build a nest with, and that was something he could fix. First, though, "What have you been feeding him?"

"We usually hand feed him a mix of fish, some mollusks, squid, that kind of thing. I made sure to follow the guidelines that the Mer Research Institute suggested."

"Dead or alive?"

"Alive, but cold shocked. He wouldn't touch any of the truly dead fish, so we found that using hypothermic ones worked better."

"Alright, first thing's first. Get some fish in there. Basic schooling fish, mackerel, perch, herring, whatever you can get through quarantine quickly. Give him something he can hunt on his own without your intervention. Frankly, I'm surprised he was even willing to eat the shocked ones, but he was probably pretty hungry. We also need to get some small rocks and plants in here. I'm talking seagrass, kelp, sargassum, literally anything that grows quickly and is easy to maintain. He'll probably start ripping it up at first, but that's why he needs it. Sound good?"

Stephanie nodded, a look of determination crossing her face. "I can do that."

"Good. Now, I'm going to go talk with your bosses." Tim smiled grimly, preparing for the coming battle. He’d been hired by the aquarium to help Big Red, and that was exactly what he was going to do.

Jason lay curled up in the sand. There wasn't any nesting material in his tank, but he'd managed to dig a sizable hole in the sand where no one could easily see him, and that would have to be good enough.

The humans had tried coming into the water a few times, but he knew better now. 

He hadn't, before. He'd let himself grow complacent, even breaching himself for the promise of food because he'd thought they'd proven they wouldn't hurt him. 

They had proved him wrong.

His hand drifted down to cup his still-flat abdomen. 

There were parts of his tail still healing, areas that he knew would scar impressively because of how violent the brute had been. He hadn't expected it.

In the past, when the door in the wall had opened, it led to a small tank that let them poke and prod him for whatever reason they wanted to poke and prod him, but last time… last time it had led to a big tank. A big tank with a bigger mer that didn’t speak the same dialect and had spent about three seconds looking at him before ripping a chunk out of Jason’s tail and carrying him to the bottom of the tank. 

He’d survived what happened next, barely, and could only be glad that the other mer had been removed after. 

He still didn’t understand why it had happened at all, but now he knew that the humans could not be trusted. 

A shift in the water had him looking up in alarm, pushing deeper into the sand when he saw a thick net being lowered to cut him off from the rest of the tank. His heart pounded in his throat, anxiety rising while he waited to see which way they would try and push him, but the net didn’t move.

A few minutes later something splashed into the water, shortly followed by a human in one of their water suits. 

He bared his teeth. If they tried to set up another of those eyes, he’d rip it to pieces just like the first.

They had a big pack with them, and more things were being lowered into the water, and… was that seagrass?

Jason forgot himself for a moment, sitting up head and shoulders out of his make-shift den to get a better look.

Big flats of seagrass were being dropped into the water along with a variety of other plants, and his heart twisted in his chest. He desperately hoped that this wasn’t a trap, that they would let him have the plants instead of using them as bribery. He’d resist if it was just another manipulation tactic, but he didn’t want to, didn’t want to deny his pup that comfort, even though it would be a while before it was born. 

It took hours for them to finish, but at last the humans pulled themselves out of the water. The net remained, and Jason was just starting to feel like his hopes had been dashed upon the rocks when it went taut, and lifted up. As soon as it cleared the surface, a great splash of water poured in, and with it came hundreds of frantically darting…


It had taken much longer than Tim hoped to get everything lined up, but by the end of the week the schooling fish had finished their antiparasitic treatment and the new flats of seagrass had come in. 

Roman, of course, had kicked up a stink when Tim had laid into him for breeding a wild mer with one born in captivity. They had ended up taking it to Oswald, the general curator for the aquarium, who could see Tim’s sense. Namely, that they would fail any APHIS inspections and lose all licences to hold protected animals. 

Tim hadn’t told them, but he was planning on reporting them anyways once he had a better game plan. From what he’d been able to find, there had been little effort put into finding Big Red’s pod a decade ago, and he had a wild, feral hope that they’d somehow be able to track them down and reunite them with Big Red. It was a longshot, but every time he looked into the tank and saw that sad lump of sand, Tim knew he’d need to dramatically change everything.  

When the day finally came to move all the new supplies into the tank, Tim was nervous. 

Everything was set up smoothly, and he’d even spotted a dark head sticking up out of the sand, but there was no telling how Big Red would react until it was all over. 

As it turned out, he reacted by not doing anything. For hours.  

Stephanie saw a hand pop up out of the makeshift nest to snatch a few unsuspecting fish, which was good, but by three in the morning it was clear that Big Red wasn’t planning on investigating anytime soon. 

He had a sneaking suspicion as to why, which was why when Stephanie asked if he was going home too he said, “No, I think I’ll spend the night here. Just in case, you know? You go ahead home though, I’ll let you know if anything happens.”

She hesitated, looking back at the glass, then waved him goodnight. 

At last, Tim was left alone in the dark. The lights had been off for hours, but now that everyone was gone, the room wasn’t filled with whispered chatter and he finally felt himself relax.

About an hour later, just as he was starting to doze, movement caught his eye. 

A figure was hovering low in the water, slowly moving towards the front of the tank. 

It was hard to see details at first, but as the mer came closer to the new features it was clear why he was called Big Red. He was bigger than any captive mer Tim had ever seen, which made sense given that he wasn’t captive-born, but still.

Mers naturally grew to be pretty large, and never really stopped growing, but Stephanie had estimated that Big Red was between twenty and thirty years old, and he was massive. At least twelve feet long from head to tail tip, which was well above average. The dark maroon scales of his tail were slightly iridescent, so the shadows played along them in streaks of deep black that would make camouflage easy. 

There seemed to be lighter areas as well, which confused Tim a little, and it wasn’t until Big Red was running his fingers through the seagrass at the front of the tank that he realized what they were. 

Thick white scars cut through the scales, some still pink and healing. The pale skin stretching across his shoulders was marred by a variety of scars, but the common theme seemed to be deep bites and claw marks. Scars that were definitely not caused by the boating accident that put Big Red in captivity in the first place.

Tim’s heart broke a little as he watched the mer pick through the different materials that had been introduced to the tank. 

He started ferrying rocks back to his divet in the sand, building up the outer wall and lining the inside with the small, smooth rocks Tim had been sure to acquire. His speed and strength were promising, and it was a relief to see him moving without any visible signs of pain given the extent of the damage. He pulled fistfuls of the seagrass out of the meadow, and Tim had to keep from cheering out loud as he watched Big Red eat three whole fish, crunching through the skulls with ease. 

He must have made some kind of noise though, because Big Red paused as he brought the end of his latest catch towards his mouth, looking intently through the glass for the first time since his cautious appearance.

Tim wasn’t sure whether to show himself or not. He didn’t know if that would scare Big Red away, or if the not knowing would send him back to his nest. 

Big Red bared his teeth, hissing loud enough that the microphones inside the tank picked it up and played it over the speakers.

Mind made up, Tim shuffled closer to the glass, hands carefully placed at his sides and forcefully casual.

Big Red moved back slightly as Tim stepped out of the shadows, and growled in warning, glaring at him with narrowed eyes. 

Tim sat down in front of the glass, purposefully trying to make himself look smaller and like less of a threat. He raised one hand in a wave, something he knew Stephanie had taught Big Red was a greeting. 

Big Red just glared at him some more, flaring his fins in challenge. After a moment more, the mer darted back to his nest, vanishing behind the now-tall pile of rocks. 

Sagging back, Tim let himself relax a little. It wasn’t much, but he had hope. Hope that he could build enough of a habitat for Big Red to feel more comfortable. Hope that if he had to stay, he and his pup would be safe from here on out. Heavens knew they needed someone on their side who actually knew what they were doing.

Jason didn’t really know what to make of the changes. All the things his tank had always been missing were suddenly just… there. His handler hadn’t tried to call him up since before everything had changed, and that new dark-haired human had been hanging around a lot. Way more than any of the other humans did, although he’d seen his handler standing by the glass at times. 

He had a real nest now, and food to hunt on his own that meant he didn’t have to rely on the humans. He spent most days hiding from the masses in his nest and moving about at night. The dark-haired human was usually there then, but he didn’t try to make Jason do anything, so he had taken to ignoring him. 

Sometimes the human would wave, sometimes he’d just watch, sometimes he’d have one of the glowing squares that humans carried around and would only look up on occasion. 

It was a curious thing, but the deciding factor for Jason was when he saw the dark-haired human yelling at one of the other humans. It was hard to tell them all apart sometimes, with their lack of fins and how often they changed their outer coverings, but this was one human that Jason was familiar with. 

He only showed up during the times the humans poked at Jason in the little tank, but he’d always made Jason’s skin crawl. He could remember the last time, when the water had tasted funny and it had made Jason too tired to fight the divers that pulled him out of his sand nest. He could remember the burning hands pressing against his belly and the straps that had held him down and how he’d been gasping for breath, suffocating with how long they held him above water.

Human behavior was always difficult to decipher, but it was clear that the dark-haired human was angry about something, and that he was winning whatever argument they were having.

It made Jason curious, and later that night, when all the other humans had left, he found himself drifting closer to the glass than usual. 

The dark-haired human was on his glowing square tonight, tapping away at something only he could see. 

Jason was suddenly struck by the realization that he looked tired. His handler looked like that sometimes, with dark marks under her eyes, and those were always the days where she wouldn’t try and get him to do cheap tricks for his food. This human reminded him of her, but this human hadn’t been around to facilitate Jason being bred.  

The human looked up, eyes widening in shock at how close Jason was, and carefully set his glowing square to the side. He offered one of those little waves, and Jason’s fingers twitched to automatically offer one back, but he curled his hands into fists instead. 

Humans did not deserve politeness. He shouldn’t even bother giving this one the time of day, he’d just been… lonely. That was all. This was a minor experiment to see what this human would try and manipulate him into doing. They were all the same.

The human made a gesture, then tipped his head in question. 

Jason had no idea what the gesture meant, so he didn’t respond. Just swished his tail slowly back and forth to maintain his position.

The human pointed at the seagrass, then the new rock piles and kelp beds. He held his thumb up, smiling happily without showing his teeth, dropped his thumb down with an exaggerated frown, then held his hand in the middle, wavering back and forth while shrugging. He was—oh. 

He was asking if Jason liked the materials. Jason was physically capable of shrugging, his handler had trained him how to do a variety of human behaviors that they always seemed excited about, but he was feeling a bit petulant, so he flared his fins and wavered them in the mer equivalent.

The human lit up. He smiled with teeth, which Jason knew wasn’t a threat but still made his hackles rise, and made a few more frantic gestures before diving over to grab his glowing square. 

He tapped around for a moment, then pressed it against the glass. 

Jason wasn’t sure what it was supposed to do, he couldn’t see any kind of picture like there normally was, and then he heard it. He strained his ears, listening for the tinny sound again, and yes. He’d heard right.

Distantly, coming from the glowing square, was mer song. A group of voices all overlapping each other, making it difficult to parse through what was being said after going so long without speaking to another mer. 

“You’re doing fine,” a laughing voice said, louder and clearer than the others. “We’re here to support you, that’s what pods are for.”

“Even if you make them think you’re a guppy, we’ll keep you safe from the sharks.” 

The overlap in the voices increased as there was some kind of scuffle, then the first voice cut through again. 

“Don’t listen to Ari. Everyone has ups and downs in courting, it’s part of the process. If they’re a good match, they’ll stick with you anyways.”

Jason’s chest hurt at the love and care that carried through the tone. He was fine most days, but suddenly, overwhelmingly, he missed his pod. There was nothing he wanted more in the world than for Bruce to hold him close, for Dick to pull at his hair. 

His fins flailed in distress, and he turned tail and bolted back to his nest. He didn’t know who this human was, but they clearly knew enough about mers to make him hurt like none of the others did.

All things considered, Tim thought that things were going pretty well. Big Red was eating, his nest was very nice for what was expected of a mer with no pod or mate, and twice now he’d come up to the glass to interact with Tim. It was very promising.

However, this was Gotham, and nothing could stay good forever. 

Tim came in on a Friday afternoon, skipping most of the school groups, and was immediately pulled aside by an aquarist who looked more than a little harried. 

“They need you in the back conference room right now. Something’s wrong.”

Tim didn’t run to get to the conference room, but he certainly wasn’t walking.

He opened the door to what looked like a war briefing, and all eyes immediately landed on him.

“Oh thank god. Tim! The bubbler in Big Red’s tank is overheating. Overall tank temperature is up four degrees Celsius and rising.” Stephanie latched onto his arm, eyes wide and hair sticking out in every direction.

“What’s wrong with it?” Tim dropped his bag in the corner, hurrying over to the table to get caught up.

“It’s overworking. We noticed that there was a lot of aeration this morning, but it’s gotten progressively worse throughout the day. The temperature started rising around eleven, and we have salt water in the freezers, but I don’t think it’ll be enough if it continues on this trend.”

Tim was a bit dumbfounded. Big Red’s tank was well over two hundred thousand gallons. The fact that the water was warming that quickly was frankly terrifying. 

“What are the options?” Mers were cold-water creatures. They could survive in warm waters for short periods of time, but there was a reason mers didn’t live in tropical regions.

The operations director took over. “Red’s tank is old. The bubbler was… well. It was designed poorly, back when the aquarium was built. There’s a manual shutoff inside the tank, but the only other way to shut it down is to cut off the electricity to the whole room, which would also turn off the water filter.”

“Which would quickly create a hypoxic environment, right.” Tim pulled one of the bubbler schematics over, thankful that the shutoff valve had already been circled in highlighter. “Where is the bubbler located? And what has Red’s behavior been like?”

“The bubbler access is along the back wall, underneath the landing platform.” Near Big Red’s nest. “Big Red has been staying near the filter dump, where the cool water is coming in.”

“Right.” That sucked. The filter and the bubbler were located on the same wall, which meant that the net couldn’t be lowered to box Red in without some serious finagling, which would give Red too much time to get out of the way. “So someone has to go in the water.”

Everyone was silent, clearly having come to the same decision long before Tim’s arrival. 

“I have the most experience working with him,” Stephanie offered quietly.

“Have you had any positive interactions with him recently?”

She scrubbed a hand over her face. “Not since before he almost killed John.” 

“Okay.” Tim knew what he wanted to do. He wasn’t really sure it was the smartest thing to do, but their options were limited and he was fairly confident that Red wouldn’t kill him on sight. “Alright, so I go in the water and turn off the valve.”

No one immediately rejected the idea, and when Stephanie opened her mouth for a token protest, he cut her off.

“Red doesn’t have negative experiences with me, and I have an up-to-date SCUBA certification. I go in, turn off the valve, and get out. Where’s your equipment?” 

Tim was suited up with a handful of waterproof power tools one hour later. His stomach was tight with nerves, but they had him attached to a tether they could use to pull him up if he tugged on it.

Strapping the goggles and mask on, he gave the all-clear and hopped into the water. It was practically frothing with bubbles, and if the situation were less serious he might have made a joke about Finding Nemo and a bubble volcano, but as it stood he could barely see a thing and his anxiety was sky high.

Studying mers for upwards of a decade had given him a healthy respect for how dangerous they were when humans threatened their territory, let alone when they were brooding with a grudge. He wanted what was best for Big Red, and he was absolutely certain that Red did not know that yet. He’d feel a lot better about all this if they could actually see the mer, but with how frothy the water was, Tim could barely see two feet in front of him. 

He had a desperate, fleeting hope that he wasn't about to be murdered, but the shifting shadows around him weren't very promising.

He swam forward through the white water, finding the back wall easy enough, and started moving along the length to find the panel he needed to access.

There was a human in the water.

Jason hadn’t been sure, at first. The water was so turbulent, and his gills were working double time in the heat, but he could taste them. 

He slipped through the water, tracking the scent towards his nest, lips curling at the idea of one of the humans invading his space. They should know better. He’d hurt the last one, but it seemed like they’d forgotten. 

He would have to remind them.

Suddenly, the source of the disturbance in the water cut off. There was still more than enough air in the water to keep it cloudy, but Jason darted towards the back wall for cover just in case. 

A dark spot against the wall caught his eye. It was the human, wearing one of their water suits, doing something to a panel of the wall. 

Anger surged inside him, further agitated by the warm water, and Jason flared his fins, muscles coiling as he prepared to lash out.

The human turned around, freezing at the sight of him, and Jason pounced. He slammed the human back against the wall, hand tight around their throat, and let out a screech that would be painful even to mer ears.

Thrashing, the human let out what could only be described as a keen, distorted through the mask, and twisted, showing—showing their belly.

Jason lurched backwards, revulsion curling in his stomach at the sign of mer submission, at the sound of ‘please, please, I’m harmless, have mercy.’ The conflicting emotions threw him off, stalled him enough that the human sank down to the sand with a soft thud, and after a moment of fumbling, pulled off the strange black thing that let them breathe under water. 

Was that…?

The human lifted a hand, waving, then brought the piece back to their mouth for a breath. 

It was the human that had asked him if he liked the nesting material, the one who had played the mer song with the pod.

The one who had stopped whatever was disturbing the water.

Jason felt a rush of guilt at having attacked him when it was clear that he had done something to help. He let out a trilling, questioning sound, not bothering with actual words, and reached out towards the human’s neck where he’d gripped so hard. 

The human didn’t fight it, just tipped his head back to bare his throat like it was nothing. The skin there was pink and irritated, but it didn’t look damaged—not that Jason had much experience with human injuries. 

He brought the breathing device back to his mouth, then held out a hand, fingers splayed, and slowly curled them into a fist.

It was baffling. How did this little human know so much about mer behavior? Their sounds and body language and gestures? He backed off, because the gesture meant ‘stop, give me space, one moment,’ but the human had now firmly cemented himself as something of interest.

The human pulled a little black box off of his belt, and a moment later it let out a string of mer song. It was choppy and not quite right, clips of other mers talking with context that didn’t fit, but still very clearly communicating, “Are you alright? Are you hurt?”

Jason could shake his head, but on a whim said out loud, “No, I’m fine,” and to his utter shock the human seemed to understand. 

The human pressed down on the box, and it let out a happy trill. Then he repeated the first set of mer songs and pointed towards Jason’s abdomen. 

He raised a hand, physically blocking his belly from sight, then wavered his fins and looked away. The human had understood last time, and Jason wasn’t about to open himself up in such a vulnerable way, no matter how helpful this human seemed. 

The human didn’t press the matter, however, and instead clipped the breathing device back in place and fiddled with the little box again. The song that played was happy, reminding him of fingers playing with his hair and peaceful nights curled up with his pod.

This time, when the human raised his hand to wave, Jason waved back. 

“Hey Duke, would you like to try and do the impossible with me? … Well, there’s this mer…”