The role of flower consumption in Howler Monkey Females’ diet: adjustment across reproductive states

In 670 contact hours, a total of 1,471 feeding sessions were recorded. From 29 documented feeding items, five were flowers from the trees of <i>Andira galeottiana</i>, <i>Bursera simaruba</i>, <i>Dendropanax arboreus</i>, <i>Gliricidia sepium</i> and <i>Spondias mombin</i>. Documented feeding items were collected and evaluated for their tannin and flavonoid content. The annual weight-based flower consumption was 12.5%, which increased to 30.3% during blooming months. The tannin content of the flower species exhibited considerable variation, with levels ranging from 0 to 2,038.0 µg/g. In contrast, the qualitative evaluation of principal groups of flavonoid content detected a pronounced presence of flavanones in all five species and flavones in three. Notably, early lactating females exhibited a higher consumption of flowers compared to non-lactating and late lactating females. Conversely, the floral tannin intake was the highest in late lactating and lowest in early lactating females. Our findings suggest that dietary choices of howler monkey females are influenced by seasonal flower availability, with polyphenols playing an important role, suggesting physiological and behavioral adaptations in response to reproductive demands.