gulp runs all tasks, not just default

Created by: enyo

I have this gulpfile:

// Include gulp
var gulp = require('gulp'); 

// Include Our Plugins
var myth = require('gulp-myth');

var cssSourceFiles = __dirname + '/css_source/*.css';
var cssTarget = __dirname;

// Lint Task
gulp.task('myth', function() {
  gulp.src(cssSourceFiles)
    .pipe(myth())
    .pipe(gulp.dest(cssTarget));
});

// Lint Task
gulp.task('watch', function() {
  gulp.watch(cssSourceFiles, function(){
    gulp.run('myth');
  });
});

// Default Task
gulp.task('default', function(){
  gulp.run('myth');
});

And when I execute gulp, it runs all tasks consecutively:

$ gulp
[gulp] Using file /Volumes/CaseFS/wetopo/tool/Gulpfile.js
[gulp] Working directory changed to /Volumes/CaseFS/wetopo/tool
[gulp] Running 'myth'...
[gulp] Finished 'myth' in 2.85 ms
[gulp] Running 'watch'...
[gulp] Finished 'watch' in 4.33 ms
[gulp] Running 'default'...
[gulp] Running 'myth'...
[gulp] Finished 'myth' in 462 μs
[gulp] Finished 'default' in 1.25 ms

If I remove the default task, it just runs myth and watch consecutively, and does not error.