Adrift

H'a'nola drifted in the strong current, gently jostled by the turbulence as he rested for a few moments. Weak sunlight refracted through the eddies above glinted around him, creating a muted cacophony of blues and pale greens that played across his spherical surface.

Like all of the males, he had spent the long winter deep in the atmosphere. Away from the light. Away from the warmth. Away from the food. Alone.

The chittering of the newborns far above had roused him from his winter lassitude, aching with hunger in the numbing cold. He welcomed the sounds that announced the end of his long isolation. Weak from his long fast, he struggled to inflate his float bladder and slowly rose, being careful to avoid collisions with the other ascending males.

Nearing exhaustion as he continued his climb, he could finally see weak shafts of sunlight filtering down to reassure him; he had survived the winter. Now would be the time to feed, regain his lost mass, and reunite with his mate.

Eventually reaching the altitude where the tan'ko plants could get enough light to grow, he began to feed. Slowly at first, being careful with a digestive system that had been shut down for so long, and then with surging gusto as his hunger overran his caution.

Finally sated, at least for a while, he prepared to make his first call for his mate. After their long separation she could be far away. He was eager to start the journey. A few other males had already begun their calls and the sounds reverberated around him.

Undulations spread across his surface as he called to his mate, Cali'tan, sending out waves of sound. His entire body vibrated to produce the complex series of changing tones and harmonics that she would recognize as his unique voice. She would respond with her own part in their shared song. Their voices would blend and they would find each other.

As he finished calling, he flattened himself into a disk lying horizontally in the rippling atmosphere so he could listen for a response, his surface a mottled grey except for bright yellow at the fringe and seventeen radial blue stripes.

He expected a response from her soon. In all the previous cycles, they had never gone very long without connecting.

#

Captain John Bowles walked into the space that had been set aside for the biology lab. In a deep baritone he asked, "Dr. Thomas, how is your research coming along?"

Dr. Jillian Thomas was surprised by his approach since his footsteps had been masked by the hum and clanking of the ship. In the confines of what had surely been a storage space before being assigned to Jillian, the only place for him to stand was practically on top of her. She was slightly on edge with the large man looming over her.

He continued, "I'm sorry you're jammed in here like this. If we had gotten more notice that you would be joining us, I could have arranged something more suitable. Or at least larger."

Jillian smiled, "That's quite alright. My grant came through late. I'm very grateful to be here."

"I wish I had been able to get over here earlier to see how you're doing. Overseeing the workers getting the mineralogy probes set up and on their way has just absorbed all of my time. I haven't had a single opportunity to come down and see what's happening with your charming ball of gas. The mining engineers are only interested in things made of rock."

The 'charming ball of gas' was the sole gas planet in the system and the focus of Jillian's work. It was the only place in the system that harbored life. Except for her small biology team, the ship's passengers were all focused on establishing mining operations on the asteroids and small planets that would pay for the trip. She had been lucky to get a ride for herself and a graduate student.

"The planet is just getting into the summer season. This will be the cycle when the young are born. Male and female adults have been separated over the winter, but will be forming mating pairs as the summer progresses. We've started monitoring them with the acoustic probes that we launched four days ago. We'll be listening as the males vocalize to attract females"

"So they put out mating calls, like birds singing in the spring? How interesting. I do hope the probes left behind by the first survey have been of use. I believe my crew was able to recover almost all of them for you."

"Yes, they did. And we're very glad to be able to do the follow up work while you're doing the prospecting. We're going to be very busy collecting and analyzing data."

The Captain smiled and put a hand on her shoulder. "We're quite happy to have you along. Please drop by to see me about anything you might need."

#

H'a'nola approached a large patch of tan'ko blooming in the warming summer sun, but was shooed away by a Tan'ch'lee Any tan'ko near the young ones were now guarded by Tan'ch'lee, the joined older couples who took on the role of gardeners, ensuring that the young had preference and that clusters of tan'ko were not devoured entirely and could regrow. Adult males, however hungry they might be, were not welcome where the young were feeding.

The females carrying young stayed in the upper layers over the winter where they could feed on tan'ko that survived from the previous summer. Although they had produced litters, by avoiding the fast over the winter and being able to eat heartily as soon as tan'ko began growing in the spring, they were in much better shape than the males. H'a'nola knew that some males had not survived the winter. Their mates would not survive the next one.

#

Jillian was so engrossed in her work that she almost didn't notice the Captain standing in the doorway. This was his third visit in a week. She forced a smile and said "Captain, nice of you to drop by. We're seeing the beginnings of the mating season."

"So these things are flying around trying to find their mates?"

"Floating or swimming, really. Not flying. The planet has a dense atmosphere. The animals break down some of the larger molecules to extract lightweight gasses that they store in a bladder. That makes them light enough to float. That way they're more fish than birds, and propel themselves rather like fish."

"Their mate seeking doesn't seem to be a very quick process."

"It isn't. They'll make preliminary contact at the beginning of the season after the young are born and the males have come back up from hibernation deep in the atmosphere. The herd becomes quite spread out over the winter, so moving towards each other will take many of them the rest of the summer. Their main activity now is feeding and putting on weight to survive next winter."

#

Ha'a'nola and Cali'tan had created their song many cycles earlier, and he thought with amusement of his initial anxieties. He wanted to craft a tone sequence that would delight a female with its beauty and complexity. Worried that he would not be able to create a song that was worthy of his ambition, he had thought long and hard, until he realized that most of the other juvenile males had already started, and quite a few of them were receiving replies from females. He fretted that he was too late to find a mate, and began his call.

Starting with a middle tone, he produced an energetic sequence to set a confident air. Against that he added long low notes for an earnest feel, and then blended in higher frequencies for what he hoped was a vibrant, exhilarating flavor. The three overlaying parts were sure to catch the interest of a female, he thought. Hearing the echoes of his own voice return from along the sound channel, he wasn't quite so sure. It was a mess. No, it was really good. Or was it?

After waiting for so long that he thought no reply would come, he heard two, both from far away. One was a nice pattern replication of his call, adequate, but with no embellishment. The other was a beautiful variation on his theme that demanded a response. He knew that a simple repetition of his first call would be inadequate, but he had to act. He thought hard about her response and blended a portion of her line into his. When she called back with her own variation, the harmony was perfect and he had his mate.

#

Brad Kelenov, the graduate student Jillian had brought with her, studied the wavering lines on the screen, watching as the computer sorted out signals from the various acoustic probes and began identifying individuals. The tones, well below the range of human hearing, were quickly processed and presented. 'Remarkable', he wrote in his notes. 'The natural sound channels and the very low frequencies let these things communicate over huge distances. That's how the herd is able to stay in touch.'

He continued to watch for a while. The acoustic signatures of two more individuals were isolated and automatically classified. He figured it would be a few more days before he had enough data to begin his analysis. He wasn't expecting much, just counting and describing a herd of herbivores that were barely subsisting in a harsh environment.

#

Hearing no response to his call, Ha'a'nola looked around the level where newly released juveniles had been feeding, gaining weight, and learning to control their color displays. A multitude of round young bodies bobbed randomly and jostled around patches of tan'ko as they fed. Almost all had already learned to extrude flattened extensions from their bodies and to use them for propulsion; their clumsy fledgling attempts at movement were both charming and amusing.

Brief flashes of color, in simple combinations, were the first attempts at communication by the newly spawned. The parentage of the young was clearly apparent in the locations, colors and patterns of their surface markings.

Although he had seen only a portion of the juveniles, H'a'nola was disappointed in not finding any of his and Cali'tan's progeny among the crowd. He had been certain that their last mating had been successful, so there should have been at least a dozen of their offspring somewhere among the multitude.

None of their progeny had yet survived their first two years to reach adulthood. But he and Cali'tan had many more cycles of breeding before they became Tan'ch'lee and produced no more young.

Females usually stayed near the young after the births; Cali'tan always had. H'a'anola expected to find her there, recovering from the long gestation, but there had been no sign of her and no answer to his call. He knew of no reason for her to go to a greater depth; the patches of tan'ko, well tended by the Tan'ch'lee, were plentiful so feeding was not a problem. The strong summer sun was producing a bountiful crop.

Still hungry after his long fast, and knowing that he would need to put on much more mass for the coming winter, he moved away from the clusters of juveniles to find an undisturbed patch of tan'ko.

He would try calling again after he fed.

#

"How are your floating cows coming along?"

Jillian closed her eyes for a moment and calmed herself. Captain Bowles' visits had become more frequent and more intrusive, disrupting her work and annoying her. Still, she needed his forbearance, no, his support to conduct her research. "They're much more complex organisms than cows. The complex vocalizations they use to locate each other over long distances are quite interesting."

"Well then," chuckled Bowles, "I stand corrected. What I really came down for is to see if you would join us at my table for dinner this evening. We haven't seen you in the officer's mess for quite a while. You need to get out of your lab once in a while and have some fun."

Jillian put on a smile and nodded. She didn't want to waste an entire evening talking to a bunch of engineers. She'd have her grad student arrange an 'emergency' sometime late in the meal.

#

H'a'nola again lay stretched out in the upper level, listening. He had repeated his call to her, putting as much energy into it as he could muster. He could hear other pairs singing their entwined songs. A few of the pairs had gotten close enough that their songs had ended as they embraced. Most of the others would be together soon, yet he heard nothing from her.

He had visited many areas where juveniles were sporting around but had not seen Cali'tan or any juveniles that could have been their offspring. Where else could he look?

Where could she be? Why hadn't she replied? H'a'nola could not imagine what could be keeping her from responding to him. Females always survived the winters when pairs were separated. It was the males that died. He must be doing something wrong, but he had tried everything he could think of. Worry was beginning to consume him. He decided to go deep again. Maybe that would help.

#

Jillian had to admit to herself that the officer's mess had a much more pleasant atmosphere than the crew cafeteria where she normally took her meals. The lighting wasn't as harsh and the noise level was lower. It was less crowded and with better table settings, too. Maybe the evening wouldn't be so bad. The food was the same, though.

The man to her right was one of the mining company leads. Powerfully built, with broad shoulders, large hands, close-cropped hair, and a square face, he would easily have fit her conception of a rough and uncultured mining engineer except for his kind eyes and gently inquisitive nature.

"So what gets you doing research way out here? What makes these animals so interesting?"

Jillian smiled and allowed herself a bit of candor. "Unfortunately, in my field if you want to get ahead, you have to find something new to work on. And if you want to find something new, you have to go way out in the field. Everything close has been studied to death. So to speak."

The man chuckled, "Well, it's the same for us. The close-in fields are getting worked out. So we go out a long way to make new finds. So what's special about your critters?"

"They have an odd mating pattern. There was an expedition about twenty years ago that initially found them, but didn't have time to really study them. Fortunately, they left monitoring probes so we now know about the two year mating cycle. It's driven by the highly elliptical orbit."

"Big seasonal changes, eh?"

"Pleased to find herself sitting next to someone who could hold a conversation, Jillian began to relax. "Yes. There's a lot of plant food available in the summer, very little in the winter when the planet is far from the star. After the summer mating season, the males hibernate for the winter very deep and below the level where the plants grow. They essentially shut down and don't eat for the whole season. And the winters are very long. The pregnant females stay higher up and survive over the winter on the plants left from the summer. The next summer the young are born and the males come back up from hibernation. That's where we are now. Then in the second winter the males and females hibernate together in the deep so the juveniles can have the food. The adults go back up the following spring and the mating season starts all over again."

"That is odd. I grew up on Farrago. Nearly circular orbit and no axial tilt, summer all year. Mating season never really stops. What are you hoping to learn about these things?"

"We started out expecting to get at the standard characteristics. Average size, life span, fecundity, mortality rates, mating behavior, things like that. Finding the data on this complicated mating cycle is a real bonus."

Brad entered the room quickly and hustled over to Jillian. "Dr. Thomas, I think you need to come down to the lab and see this."

Jillian pretended to be annoyed at the interruption. "Something in the acoustic data?"

Brad nodded vigorously and turned to leave. Jillian excused herself and strolled out after her student.

#

Hovering at a level so deep that the light was almost extinguished, anxiously awaiting Cali'tan's reply, he saw the ovoid shape of a newly spawned juvenile descending, gleefully flashing bright yellow. The joy of discovering the ability to control depth often led the young to unreasonably bold or outright foolhardy plunges to depths from which they could not recover. At that age a youth could easily drop to a depth where the pressure would overcome whatever it could create in its float bladder. H'a'nola displayed pulsing red and blue around his outer rim, hoping that the tang of danger signals would deter the youngster. Whether it was his warnings or the child's own sense of self preservation, H'a'nola could see sudden, frantic efforts by the juvenile to recover buoyancy as it passed by in its descent. The child was probably already past the point of rescuing itself and would soon perish.

H'a'nola remembered his own narrow escape from that fate, having stopped at a limit he had not understood, struggling to regain control. Terrified at the consequence he then saw before him, he reversed his plunge with desperate exertions. Although his progress came in tiny increments, he finally succeeded in stopping the downward rush and started to move slowly upwards. Regaining a safe depth, he drifted, exhausted, vowing to never repeat the foolish maneuver. Only starvation over their first winter took the lives of more juveniles than such dangerous antics. He knew that many of his own progeny this cycle would suffer that fate, but surely not all of them. Cali'tan herself knew better than to descend too fast. What else could be going wrong? It didn't make sense.

#

As they entered the biology lab, Jillian thanked Brad for executing the pre-planned interruption and began to seat herself at her desk.

Waving her over to his terminal, Brad said, "There really is something you should see. I'm seeing male/female pairs starting to match up in the acoustic data. But it's not just the males vocalizing to attract a mate. The females are calling back."

Jillian swung her chair around. "How do you know that you're seeing a response to the initial vocalization?"

"I've been running the acoustic data through the pattern recognition algorithms. It's been able to identify pairs whose calls correlate. The female response is a variation on the theme of the male's vocalization. When I put the two calls together, they overlay really well. They're doing duets. The time delays between the call and the response matches the distance between the two animals. I've been tracking the locations. The calls that correlate also converge towards each other as the animals swim. And they go right into it, like they've done it before."

#

He continued to float quietly, a large disk nudged by small turbulence, listening. This far up in the atmosphere, sunlight warmed his upper surface. He could hear the songs of other pairs. The intervals between calls and responses were getting shorter as mates approached each other. Some had gone quiet as they got close enough to join. And yet, he had heard nothing from Cali'tan. He had been listening for long enough since his last call. If she had replied he would have heard by now. Something must be preventing his calls from getting to her.

He knew that he should eat. He needed much more mass before the winter to make sure the two of them would survive it, but somehow he did not feel like eating.

Maybe he should move further south. Perhaps she was caught in an eddy that deflected the sound. She would realize that, he was sure, and would move out of it. She had to be somewhere. He had to be patient.

#

Brad called Jillian over to his terminal, "Dr. Thomas, I think you need to see this."

Jillian walked over and stood behind him. "Something more in the acoustic data?"

"Yeah. I was matching the signatures of individuals in the current data with those of the survey twenty years ago to see if any of the animals from then are still alive. Turns out that almost half are. That's a lot more than I would have expected."

"Hmmm, yes. I wouldn't have been surprised to find that none had survived that long. Match the acoustic with the visual identifications when we get that data in to make sure we really are looking at the same individuals." She began to move back to her own work station.

"But hold on. That's not the most interesting thing. I wondered if the old guys had a preference for their own age group, or if they, well, went after the younger females. So I ran a match to see how many of them ended up with mates that were also oldsters. They all did."

Jillian was surprised. "So, it looks like they're choosing mates about the same age. That's a bit odd."

"It's not just that mates are the same age. I ran a match to see how many of them ended up with the exact same mate this year as before." He tapped an icon on his screen.

Jillian stared at the result. This was fantastic.

It was all of them.

#

The storm that had just passed had been severe, its effects going deep. Such storms were common this late in the season. H'a'nola knew that such a large storm might have disrupted the sound channels and that he could expect another one. If he and Cali'tan had been close it would not have been a problem, but they were obviously still far apart. He decided to go deeper before calling again. Maybe his voice would carry better from the deeper layer. He hoped so.

#

Jillian spoke to Brad across the small room. "Most of the mating pairs are getting close to each other. I want to be sure we can match the visual pair identification with the acoustic data."

#

A long, thin object, rounded on one end and reflecting the little sunlight that penetrated to this depth, moved past H'a'nola, slightly above him. He could not see what made it move since it had not extended any fins and remained rigid. He had no idea what it was. It did not appear to be edible and, although it circled him a few times, did not get in his way, so he ignored it.

A sudden burst of light from the thing startled him. He displayed warning signals on his surface, but nothing further happened. In a while, the object moved off.

He wondered, could that object have something to do with Cali'tan's silence? The flashing light had been frightening, but did not seem dangerous. He hoped Cali'tan had not been scared into silence by it.

#

Brad thumbed his datpad and the wall display sprang to life. "We're about halfway done with the optical survey. The males are growing at an amazing rate. There are several that I've seen multiple times. Even though they must have come out of hibernation only slightly larger than the females, at the rate they're growing they'll be ten times as large by the end of the summer."

"That might be linked to the male/female pairings over the next winter. Keep tracking that. What about the comparisons of visual identifications with the acoustic data?" "I've started matching the skin patterns with the records. The results are preliminary, but high enough to have confidence that we're seeing many of the same creatures. It confirms the acoustic results."

"Very good. Keep at it. We're not under time pressure yet on the observations, but I want to get them done. Who knows when the ship jockeys will decide to move.

"There is one more thing," said Brad. Some of the skin patterns change. I've only seen it on a couple of them and it seems to be just temporary."

"When does it happen?"

"Twice I saw it when a mating pair got close to each other. It was like they were communicating using their skin colors. They took turns putting on displays. I couldn't let the probe stay very long to watch because I still had a lot of ground to cover, but I thought it was interesting. It might be some sort of courtship ritual. There was another time when I took a still of one of them. It was deep and I used the flash. The thing reacted like it was alarmed and started changing its markings. The basic markings were still there, but some other coloration showed up for a while."

#

The juveniles had quit their chattering and the world was getting quiet. Here in the deep he could hear the songs from the few pairs that had not yet met up. Some were clearly quite distant, so the sound carried well down here. And yet there was no response from Cali'tan. H'a'nola hardly had the energy to call again. He had no appetite and had not been eating even though he knew he needed more mass to get the two of them through the winter. Why couldn't he find her? What was he doing wrong?

He missed Cali'tan, talking to her, being near her. He longed to feel her body as he wrapped himself around her, protecting her and preparing for the dimming light and scarce food when they went deep into the cold and dark for the winter. He missed the gentle ecstasy of becoming one and sharing warmth as they slowed each other down and entered the merged dreaming of the joined hibernation. He hated the cycles he spent alone in the deep. When they were beyond mating, they would unite forever and become Tan'ch'lee. That would be joy.

#

Brad brought a tablet over to Jillian's desk. Showing the data display to his mentor, he said, "Visual identification ninety percent complete. All individuals that the acoustic identifications found in the previous observations showed surface markings that match the current data. The pairs match up as well in the visual data as the acoustic data. I think you have the proof that they mate for life."

Jillian smiled, "Excellent. The video data shows something else interesting. When a pair meets, the male wrap himself around the female. He's probably an insulating blanket for her when they go deep for the winter. That's how the females survive the cold.

Brad smirked, "Well, that explains the females interest in mating for life."

"What about the visual IDs that haven't been matched in the acoustics?"

"We have thirty seven females that haven't vocalized at all. Apparently they wait for males to start. My guess is that their mates didn't make it through the winter."

"Thirty seven. That sounds about right for the mortality rate."

"I wonder if the unpaired females will make it through the next winter."

Jillian shook her head. "I doubt it. The pairing strategy seems to be essential to the winter survival of the females. Anything else?"

"There is the one unpaired male that is still vocalizing."

Jillian nodded. "Given what we know about them, we shouldn't be surprised."

#

H'a'nola was exhausted from calling. He was underweight and would not survive the winter, but he could not give up looking for her. The world was getting quiet; all of the others had found their mates and were settled into their winter joinings. He hated the thought that she would die because he had failed. He missed her.

#

The Captain approached Jillian, looking apologetic. "I'm afraid we're going to be breaking orbit soon and relocating to the outer section of the system. The interior bodies have been mapped and distances to the outer planets are too great to run surveys from here. I hope you've gotten the data you need."

"We're able to make several important observations well beyond what the earlier survey accomplished. These creatures mate for life. They have complex audio and visual communication. Our dissection of the one we brought up several months ago was very revealing on their basic biology. Fortunately, it was a female ready to birth a litter of almost two dozen, so we had a lot of material to work with. We'll be studying those samples for a long time."

The Captain grimaced. "It did make quite a mess in the starboard loading dock. I was glad when we were able to get that cleaned out, although it still smells. Did you learn everything you wanted to about these creatures?"

"Not hardly. These animals have complex communications, both vocal and visual that we need to decode. The strategy for survival over the winter has to be driving the pair bonds and I want to know more about that. We don't understand the role of the male/female pairs that remain linked all the time."

"Well, I hope that you'll be able to have a bit more free time now that your data collection is completed."

Jillian replied, "We have a lot more data analysis to do and I'll be busy writing up the results for the rest of the trip. And I'll be preparing another grant application. We need to come back. Next time I want to capture a male for dissection."

The Captain frowned at the thought of the mess that would make. "I'm glad that the voyage has been productive." He turned and left the lab.