Reading the Mara River Before a Crossing

The question I am asked most often, usually in an email eight months before anyone gets on a plane, is what day the wildebeest cross the Mara. I understand why people ask it. It is the shape of every other thing we book — a flight has a time, a table has a time — and it feels reasonable that an animal migration would too. It does not. What I can tell you instead is where the herd will be in a given fortnight, which is a real and useful thing, and then what happens on the bank once we are standing on it.

A crossing is a negotiation. Several thousand animals arrive at a river they do not want to enter, mill about for anything from twenty minutes to two days, and then one of them goes and the argument is over. Everything a guide does at Kogatende between June and October is an attempt to be parked in the right place when that one animal moves.

The river decides, not the calendar

The herd is in the north when the southern plains have dried out and the north has not, and that timing moves by weeks from year to year. In a wet year the animals hold on the short grass far longer and arrive late; in a dry one they are strung along the river by the middle of July. So we do not sell a date. We sell a window, and inside that window we move.

The river itself matters as much as the herd. A Mara in flood after rain in the Kenyan highlands — which can be raining a hundred kilometres away, under a sky that is perfectly clear above us — is a different proposition from a Mara you can wade. High water pushes the animals to the shallower, wider points and makes them hesitate for longer. Low water opens crossing places that have been unused for a month and can turn a three-hour stand-off into ten minutes.

The crossing points themselves are old. They are cut into the bank by decades of hooves, they have names and numbers that every guide on that stretch of river uses, and they do not move. What moves is which of them the herd fancies today.

What a false start looks like

By mid-morning there may be four thousand animals on the ridge above the water, walking down toward it in a column that keeps re-forming. This is the part that tests people. The column reaches the lip of the bank, the front animals stop, the ones behind keep coming, the pressure builds, and then something — a crocodile surfacing, a vehicle door, a hippo yawning, nothing at all — turns the whole front rank around and the column walks back up the hill. Then it does it again. Then it does it a third time.

You learn to read the pressure rather than the movement. The signals I watch for, in roughly the order they arrive:

The mistake is to think the herd is deciding whether to cross. It has already decided. It is deciding when, and it will change its mind eleven times before it means it.

Where we put the vehicle

This is the part of the craft that guests do not see and that changes their morning completely. We arrive early, we get high, and we watch which of the cuts the front of the column is drifting toward. Then we park downwind and off the approach line, usually further back than a guest would choose, and we turn the engine off.

Vehicles pressed against the water at the crossing point are the single most common reason a build-up collapses. It is also, unfortunately, what the herd is often photographed against. If we are the eleventh vehicle at a point, we leave and take the next one along, because a crossing at a quiet cut a kilometre downstream is worth more than a front-row seat at one that will not happen. That decision is easier to make at six in the morning than at two in the afternoon, which is one of several reasons we go out early and stay out.

The other reason for distance is that a crossing is not tidy. Animals go in at a point and come out over three hundred metres of bank. If you are parked at the entry you see the entry. If you are parked a little wide you see the entry, the swim, the exits and the calves that miss them, which is the whole story rather than the poster.

The part nobody photographs

After the last animal is across there is a half hour that I think is the real reason to be there. The far bank is a mess of wet, exhausted animals that have lost each other. Cows stand at the water calling for calves that went in fifty metres upstream. Some of those calves come out and find them, and the noise those two animals make is not a sound you forget. Some do not.

It is not a comfortable half hour and I do not dress it up for guests beforehand. Something on the order of one animal in two hundred does not get out of the water, and every crocodile and vulture on that stretch of river knows the date better than we do. People who come expecting a spectacle sometimes go quiet. People who come expecting an ecosystem tend to stay quiet for a different reason.

What I would tell you to expect

On a nine-day trip timed to the season, in a good year, at the right stretch of river, I would say you have a strong chance of one crossing and a reasonable chance of two. I would not promise you three, and I would be wary of anyone who does. What I will promise is that the days that do not produce a crossing are not empty days: the northern Serengeti in season holds the highest concentration of large predators anywhere in the ecosystem, precisely because a million and a half animals are standing next to a river.

We give you two nights on the river rather than one for exactly this reason. Not because the second morning is more likely than the first, but because two mornings is twice as many chances at something that runs on its own clock — and because on the second morning you already know what the build-up looks like, and you will see it coming before I say anything.