Sharks of Onslow County
In the last few weeks, the water along the edges of Onslow County has felt different.
Not because the water itself has changed—but because something beneath it has become harder to ignore.
Schools of cownose ray (Rhinoptera bonasus) move just below the surface nearshore, their wingbeats lifting faint clouds from the bottom as they pass. In the soundside shallows, where the water thins over sand and mud, Atlantic stingray (Hypanus sabinus) settle into the substrate, half-buried and nearly invisible until a step comes too close and the outline breaks.
People are seeing them more often now—but they’re also reacting to them.
A pause mid-step in shallow water.
A quick shift backward when something moves.
Fishermen lifting a line and stopping for a second longer than usual—not what they expected to find.
There is awe in it.
And sometimes hesitation.
Because the same thing that makes them easy to notice now also makes them easy to miss.
The question follows quickly:
Are there more of them this year?
Maybe.
But that question lingers longer than the answer.
As spring settles in along the North Carolina coast, the system begins to reorganize.
Water temperatures rise, and with that rise comes a shift in metabolism. Rays—like many coastal species—become more active as conditions move into a narrower range that supports feeding and movement (Smith & Merriner, 1987; Schwartz & Dahlberg, 1978).
For cownose rays, this seasonal transition includes a northward migration along the Atlantic coast, bringing large groups into nearshore and estuarine waters (Smith & Merriner, 1987).
But movement alone does not explain what people are seeing.
What matters is where that movement meets the structure of the environment.
The water does not always look the same—some days it is flat and clear enough to see straight to the bottom, and other days the slightest movement turns it cloudy, changing what can be seen and what remains hidden (Peterson et al., 2001).
And beneath all of it is food.
Cownose rays move through the shallows, sweeping across the bottom and disrupting what lies beneath them, crushing clams, oysters, and other shelled invertebrates with broad, flattened tooth plates (Collins et al., 2007; Fisher, 2010).
Atlantic stingrays hold low against the bottom, burying into the sand as they feed and working within the sediment itself—not moving across it—uncovering and drawing in small invertebrates hidden below (Snelson et al., 1988; Schwartz & Dahlberg, 1978).
Where prey is accessible, rays follow.
Where prey is concentrated in shallow, warming water, rays do not just pass through—they stay, turn, feed, and linger.
And in doing so, they cross into the same narrow band of space where people enter the water (Bangley et al., 2018).
They are not simply “here more.”
They are here in ways—and in places—that make them visible.
When a ray feeds, the bottom does not remain the same.
A cownose ray moving across a flat is not just searching—it is actively restructuring the surface beneath it. As it passes, the bottom is turned over behind it, patches of sand and mud disturbed where clams and other buried life have just been uncovered and crushed (Peterson et al., 2001; Smith & Merriner, 1985).
Atlantic stingrays leave a different kind of trace. Where they settle, the surface shifts more subtly—small depressions, softened patches, places where the sediment has been worked rather than overturned, as buried invertebrates are uncovered and drawn in (Snelson et al., 1988; Schwartz & Dahlberg, 1978).
This is bioturbation—the bottom being reworked by the animals moving through it and within it (Thrush & Dayton, 2002).
As they feed, the bottom lifts into the water—fine particles rising and hanging there, turning clear water slightly cloudy (Thrush & Dayton, 2002).
The water does not stay still—the bottom here is constantly shifting, the way much of this coastline does, even when it appears unchanged.
And neither does the system.
Oysters and clams quietly filter the water as they feed, and when their numbers shift—even in small areas—the water and everything moving through it begins to change with them (Newell, 2004; zu Ermgassen et al., 2013).
In places where rays have been feeding, those filtering communities can be reduced or redistributed (Peterson et al., 2001).
Not removed entirely—but changed.
And that change does not stay in one place.
It moves outward, carried in the way the water looks, the way it settles, and what it can hold.
Rays do not sit at the top of the system, and they are not at the bottom of it.
As mesopredators, they feed on what is buried in the sediment, but they are also available to what moves through the water above. That position—between—links parts of the system that do not often meet directly (Myers et al., 2007; Heithaus et al., 2008).
What they do in that space matters.
As cownose rays move through andAtlantic stingrays work within the bottom, they are not just feeding—they are shaping what persists there. Clams, oysters, and other invertebrates do not simply accumulate unchecked. Their numbers are reduced, redistributed, and in some places kept from becoming dominant (Peterson et al., 2001).
Movement like this doesn’t stay in one place for long.
That pressure shapes the bottom itself.
Bivalves filter the water. Invertebrates stabilize sediment. When their abundance shifts, the system responds—sometimes toward clearer water, sometimes toward more suspended material, depending on what remains and where (Newell, 2004; zu Ermgassen et al., 2013).
Rays do not create those conditions alone—but they influence which direction the system moves.
At the same time, they carry that energy upward.
Juvenile sharks moving through these shallow waters encounter not just prey, but a system already in motion—areas where the bottom has been disturbed, where feeding has recently occurred, where something has been uncovered or displaced (Bangley et al., 2018).
And in some cases, the rays themselves become part of that exchange.
This is what it means to sit in the middle.
Not just connecting layers—but regulating how energy and movement pass between them.
If that middle shifts, the balance does not disappear.
It changes direction.
There is a moment, standing in shallow water, when the bottom stops feeling like something you can trust.
What looked like sand shifts.
What felt still is no longer still.
Sometimes you notice it in time—a shape lifting away, a shadow moving just beneath the surface. A plume of fine sediment rising to the surface under a paddleboard with a trail following it.
Sometimes you don’t.
A step comes down where something is already settled.
Hidden in the sand.
Working within it.
The reaction is immediate.
Surprise first. Then pain. Then the realization of what was there all along.
It is easy, in that moment, to think something unexpected has happened—the same kind of sudden awareness that comes when something just beneath the surface reveals itself.
But what you are stepping into is not a single event.
It is a convergence.
Water temperatures have risen, bringing rays into the shallows as they feed and move through these systems (Smith & Merriner, 1987; Schwartz & Dahlberg, 1978).
Tides narrow the space, concentrating movement into a thinner band of water.
The bottom has already been worked—turned by cownose rays moving through, disturbed by Atlantic stingrays holding within it.
And at the same time, people have returned to the water.
For a brief window, all of it overlaps.
Not more.
But more visible.
It feels sudden because you are standing at the point where all of these things meet.
And for a moment, the system lets you see it.
Bangley, C. W., Paramore, L., Dedman, S., & Rulifson, R. A. (2018). Delineation and mapping of coastal shark habitat within a shallow lagoonal Estuary. PLOS ONE, 13(4), e0195221. https://doi.org/10.1371/journal.pone.0195221
Giaroli, M. L., Byrne, I., Gilby, B. L., Taylor, M., Chargulaf, C. A., & Tibbetts, I. R. (2024). The distribution and significance of stingray feeding pits in Quandamooka (Moreton Bay), Australia. Marine and Freshwater Research, 75(18). https://doi.org/10.1071/mf23247
Heithaus, M. R., Frid, A., Wirsing, A. J., & Worm, B. (2008). Predicting ecological consequences of marine top predator declines. Trends in Ecology & Evolution, 23(4), 202-210. https://doi.org/10.1016/j.tree.2008.01.003
Kolmann, M. A., Huber, D. R., Motta, P. J., & Grubbs, R. D. (2015). Feeding biomechanics of the cownose ray, Rhinoptera bonasus, over ontogeny. Journal of Anatomy, 227(3), 341-351. https://onlinelibrary.wiley.com/doi/full/10.1111/joa.12342
Myers, R. A., Baum, J. K., Shepherd, T. D., Powers, S. P., & Peterson, C. H. (2007). Cascading effects of the loss of APEX predatory sharks from a coastal ocean. Science, 315(5820), 1846-1850. https://doi.org/10.1126/science.1138657
Newell, R. I. (2004). Ecosystem influences of natural and cultivated populations of suspension-feeding bivalve molluscs: A review. 23(1), 51–61. Journal of Shellfish Research, 23(1), 51-61. https://go.gale.com/ps/i.do?id=GALE%7CA118543914
Peterson, C. H., Fodrie, J. F., Summerson, H. C., & Powers, S. P. (2001). Site-specific and density-dependent extinction of prey by schooling rays: generation of a population sink in top-quality habitat for bay scallops. Oecologia, 129, 349-356. https://link.springer.com/article/10.1007/s004420100742
Schwartz, F. J., & Dahlberg, M. D. (1978). Biology and ecology of the Atlantic Stingray, Dasyatis Sabina (Pisces: Dasyatidae) in North Carolina and Georgia. Northeast Gulf Science, 2(1). https://doi.org/10.18785/negs.0201.01
Smith, J. W., & Merriner, J. V. (1985). Food habits and feeding behavior of the Cownose ray, Rhinoptera bonasus, in lower Chesapeake Bay. Estuaries, 8(3), 305. https://doi.org/10.2307/1351491
Smith, J. W., & Merriner, J. V. (1987). Age and growth, movements and distribution of the Cownose ray, Rhinoptera bonasus, in Chesapeake Bay. Estuaries, 10(2), 153. https://doi.org/10.2307/1352180
Snelson, F. F., Williams-Hooper, S. E., & Schmid, T. H. (1988). Reproduction and ecology of the Atlantic Stingray, Dasyatis Sabina, in Florida coastal lagoons. Copeia, 1988(3), 729. https://doi.org/10.2307/1445395
Thrush, S. F., & Dayton, P. K. (2002). Disturbance to marine benthic habitats by trawling and dredging: Implications for marine biodiversity. Annual Review of Ecology and Systematics, 33(1), 449-473. https://doi.org/10.1146/annurev.ecolsys.33.010802.150515
Zu Ermgassen, P. S., Spalding, M. D., Blake, B., Coen, L. D., Dumbauld, B., Geiger, S., Grabowski, J. H., Grizzle, R., Luckenbach, M., McGraw, K., Rodney, W., Ruesink, J. L., Powers, S. P., & Brumbaugh, R. (2012). Historical ecology with real numbers: Past and present extent and biomass of an imperilled estuarine habitat. Proceedings of the Royal Society B: Biological Sciences, 279(1742), 3393-3400. https://doi.org/10.1098/rspb.2012.0313
