The format of the Messenger Dog trials is shortly described here, this page is a collection of photos illustrating this sport.
The Belgians featured on this page are:
The Messenger Dog competition is a team sport that requires a dog and two handlers. Ideally, the dog is equally bonded to both handlers. Often the handlers are a husband and a wife, a parent and a (teenage or older) child, or very good friends.
Here you can see Apollo's team: Merja, Tepe and Apollo. (This picture is not yet available as a larger version.)
To start training for the Messenger Dog trials, the first thing to do
is to teach the dog (preferably already a puppy) that it is great fun
to run from one handler to another. This has to be done in a kind of a
controlled manner, though: the puppy should not dart back and forth
between the two handlers, but instead stay for a while with one handler,
relax a bit, and then return. This way the puppy learns that it is
expected to actually reach the person, not just to come close (and
then return!)
The easiest way to do the first exercises is to go to a park etc. with
no other people or dogs around. One handler, "H2", walks with the puppy
to a distance where they can still see and hear the other handler "H1"
who remains still. H2 and the puppy wait for a while, then H2 gives
the puppy a command ("run!" or whatever), and H1 starts calling the
puppy's name. When the puppy reaches H1, it gets treats and lots of
praise. H1 sits down to relax gently holding the puppy with him, and
after a while sends it to run to H2. The puppy is sent to run from
one handler to the other (at least) 5 times, so that it finally stays together
with H1 and they wait for H2 to return to them, and then they
all rejoice being together again! (They can both give the puppy treats etc.)
Then they can go home and do some more bonding :-)
When the puppy has repeated the exercise so many times that it
clearly knows what the handlers expect it to do, the team can start
practising in a forest and gradually start using longer distances.
For the first time when the dog does not see H1 while with H2 he
should still be able to hear H1's calls, and gradually the distance
gets longer so that they can't even hear each other.
When the distances get longer, it is very important to make sure
that each handler knows what the dog is doing. Usually the handlers
make a schedule for sending the dog to run, or they can call each
other's mobile telephone to discuss the plans. The most important thing
is that the dog should never return to one handler without having
reached the other handler first! Nowadays this is often checked by calling
each other's mobile telephones, but especially in the older days we
used "flags" that one handler tied to the dog's harness and which the
other then had to remove. So if the dog returned to the handler who
always tied the flag still wearing the flag, he/she knew that the dog
had not reached the other handler, and vice versa.
Here Sumu is sent to run to the other handler. Sumu wears the
working dog harness, and has a white "flag" tied to it to signal that
she had actually reached this handler, Anna. Anna talks to Sumu
in a very excited voice: "Where is Arto? You should go and find him!
You'll get lots of goodies!" etc. and then gives the command: "run!"
Sumu's other handler, Arto, then receives Sumu with lots of treats and
praise and removes the flag from the harness. They relax for a while, Sumu
is offered some water to drink, and after a while Arto sends Sumu back to Anna.
In this picture you can see Anna receiving Sumu with lots of praise!
In competitions the dog is not only requested to run from one handler
to another, but must also behave well while waiting (no barking or
whining -- difficult for many Belgians!), must heel promptly to the
starting line, must wait for the handler's command to make a start, etc.
Also, the handlers H2 change their position while the dogs are with
the handlers H1 so that the dog must also be able to do some tracking
(this is actually not very difficult because several people walk the
same track, but it requires that the dog is confident to find the
handler in the new position and does not want to return to the other
handler instead).
There can be many dogs (5-6 is common, but there can be as many as 10 dogs),
so one trial can take a long time. Also, there is an obedience trial
and an article search that the team has to pass either before or after
the "message delivery" part on the same day!
A Crash Course to Training a Messenger Dog