Holidays in Comoros

Official national public holidays. Regional and religious observances may vary by area.

About Time in Comoros

For About Nine Hours Each Night, Coelacanths Leave Their Lava Caves to Hunt

Off the steep western coast of Grande Comore, one of the world's most unusual daily biological schedules begins shortly after sunset. West Indian Ocean coelacanths, Latimeria chalumnae, spend daylight hours sheltering in submarine lava caves, then emerge individually at night.

Acoustic-telemetry research tracked nine coelacanths for periods ranging from one to sixteen nights. Their active phase averaged about nine hours. Most left their daytime refuges shortly after sunset and returned before sunrise.

The night was not spent swimming rapidly through open water. Coelacanths are exceptionally slow-moving predators. Tracking data estimated an average swimming speed of about 3.2 meters per minute, and many individuals travelled no more than roughly three kilometers during a night.

Depth changed with the same daily rhythm. Most movement occurred between approximately 180 and 400 meters, often below the level of the daytime caves. Researchers recorded the fish primarily between 200 and 300 meters, but larger individuals occasionally made much deeper excursions. One telemetry record reached 698 meters.

The animals also used temperature as an effective boundary. They spent most of their time in water around 15 to 19 degrees Celsius and rarely entered water warmer than about 22 degrees. Around Grande Comore, warmer surface water helps explain why suitable habitat begins relatively deep along the volcanic slopes.

During daylight, the pattern reverses. Earlier submersible surveys found several individuals sharing the same caves without obvious aggression. Researchers could recognize individual fish from their distinctive pale body markings and found strong fidelity to the same coastal habitat over years.

The result is an unusually clean daily clock: darkness opens the hunting period, dawn closes it. For an animal lineage often described through geological time, some of the most detailed knowledge about its living ecology is measured in hours.

In April 2005, Karthala Turned a Crater Lake into Lava, Then Water Returned Within Weeks

Karthala's 2005 activity produced one of the most remarkable short geological chronologies in the Comoros. Before the eruption, Chahalé crater near the summit contained a water lake that had occupied the depression since the 1991 eruption.

On 16 April 2005, the volcano moved rapidly from seismic unrest into eruption. The Karthala Volcano Observatory recorded a seismic crisis beginning at 08:12. Long-period events appeared from 09:14, and by 10:55 a continuous tremor signal was being recorded. Around 14:00, residents heard rumbling from the volcano, and an ash column became visible shortly afterward.

Ash began falling on the eastern side of Grande Comore around 16:00 and continued through the night. At 21:05 on 17 April, tremor amplitude dropped sharply. During the night, activity fluctuated, with another maximum around 01:40 on 18 April and a minimum around 04:30.

At 08:30 on 18 April, an overflight revealed how radically the summit had changed. The water lake was gone. A lava lake occupied the Chahalé crater instead, with parts of its surface still molten and incandescent.

The transformation did not remain static. By the following day, much of the lava surface had chilled. On 20 April, observers found ash deposits ranging from only millimeters near the coast to about 1.5 meters near the summit. Heat beneath the solidifying crust continued to turn incoming groundwater into steam.

Then the crater began moving back toward its previous state. During a field visit on 8 May, observers recorded the renewed presence of water inside Chahalé. In less than a month, the same depression had passed from a water lake to a molten lava lake and back toward a water-filled crater.

The cycle repeated later that year. Seismicity intensified again during the second half of 2005, culminating in another eruption on 24 November. On 26 November, investigators found an almost entirely molten lava lake inside Chahalé, where a water lake tens of meters deep had existed before the eruption. By 30 November, about 80 percent of the lava surface had solidified, and by 5 December only small active areas remained.

Karthala therefore recorded time through changing states of the same crater: water, eruption, lava, cooling, renewed water, then another eruption only seven months later. The sequence is much more informative than simply listing 2005 as an eruption year.

Ylang-Ylang Quality Can Change Between 07:00 and 11:00

The Comoros are one of the world's principal centers of ylang-ylang essential-oil production. For this crop, the hour when flowers are picked and the delay before distillation are not minor logistical details. They can alter both oil yield and chemical composition.

Recent research on ylang-ylang flowers examined harvests made at 07:00, 11:00 and 15:00 and compared flowers distilled immediately with flowers stored for 4, 8, 24 and 30 hours before processing.

The results showed that short storage was relatively forgiving. Oil yield did not fall significantly during the first eight hours. After 24 and 30 hours, however, losses became much more important. The aromatic fraction of fresh petals also declined substantially with prolonged storage, falling from about 73.66 percent in fresh material to 57.02 percent after extended storage.

Harvest hour mattered as well. Flowers collected at 07:00 or 15:00 and processed quickly produced better overall yield and chemical profiles than flowers picked around 11:00 in the tested conditions. Midday heat therefore does not simply make harvesting less comfortable; it can change the raw material entering the still.

This creates a production chain measured in hours rather than seasons. Flowers reach the correct maturity, workers pick them during a preferred daily window, transport begins immediately, and distillation has to start before storage changes the volatile compounds that make the oil valuable.

The process is especially important because ylang-ylang is not a minor local product. CIRAD research identifies the Union of the Comoros as a leading producer in the southwest Indian Ocean, with ylang-ylang, vanilla and cloves together accounting for most of the country's traditional export crop value.

The useful clock is therefore chemical. A flower cut in the morning is not identical to the same flower after a day in storage. The market value of the final oil begins changing from the moment harvest starts.

Comorian Law Starts the Ramadan Administrative Clock One Week Before the Month Begins

Time enters Comorian law directly in the regulation of religious practice. Law No. 08-011/AU of 27 June 2008 contains a specific rule for the period immediately preceding Ramadan.

Article 7 states that one week before the beginning of the sacred month, the minister responsible for Islamic affairs, after consultation with the Council of Ulema, is to announce by official order the instructions that must be observed during the period.

The provision is notable because it creates a legal countdown attached to a lunar religious calendar. Ramadan does not occupy the same Gregorian dates every year. Its position moves through the seasons because the Islamic calendar is based on lunar months.

Administrative preparation must therefore follow the religious calendar rather than a permanently fixed date in January, March or another civil month. Once the beginning of Ramadan is established for a particular year, the legal one-week interval immediately before it becomes operational.

The same law recognizes several other named religious practices, including Maoulid, Dhikr and the fast associated with 27 Rajab. These observances also belong to a calendar whose dates shift through the Gregorian year.

This creates two overlapping systems of public time. Civil administration operates through dated laws, decrees and official orders. Religious observances advance according to the lunar calendar. Article 7 connects the two by requiring government action at a defined interval before a moving religious date.

Comorian Labour Law Defines Night as 19:00 to 05:00

The Labour Code gives another legal definition of time, this time inside the working day. Article 121 limits ordinary work in public and private establishments to forty hours per week and eight hours per worker per day.

Agriculture is treated differently. The Code specifies 2,340 working hours per year, equivalent to forty-five hours per week, reflecting the different annual organization of agricultural work.

The law then defines night work with exact clock boundaries. Article 124 classifies work performed between 19:00 and 05:00 as night work. A night worker is entitled to a minimum rest period of twelve hours.

The Code goes further by distinguishing the deepest part of the night. Hourly pay increases apply to qualifying night work, with a higher premium required for work performed between 23:00 and 05:00 than for the surrounding night hours.

That means 22:30 and 23:30 can belong to the same shift but not to the same legal pay category. Midnight is not what defines the boundary. The law creates its own internal division of the night at 23:00.

The Code also regulates lost working time. Hours missed because of collective interruption caused by accidents, severe weather, force majeure or specified calendar situations may be recovered, but recovery is limited to no more than one additional hour per day and eight hours per week.

Working time is therefore not simply recorded after the fact. Comorian law divides the week, the day and the night into different legal intervals, then assigns different limits, rest requirements and compensation rules to each.

Mohéli's Green Turtles Nest All Year, but May Is the Peak

On the beaches near Itsamia on Mohéli, green turtle nesting does not fit a simple season in which animals arrive for a few weeks and then disappear. Long-term monitoring found nesting during every month of the year.

The intensity, however, changes dramatically. Researchers monitored five neighboring beaches from January 1999 to June 2007 almost daily, with additional observations continuing irregularly through 2014. Nesting rose during the austral winter, with the main peak extending from March through August and the highest average activity in May.

The scale of the monitoring makes the seasonal pattern unusually robust. Between 2000 and 2006, observers recorded 63,164 successful nesting events. After correcting for missing observations, researchers estimated approximately 69,630 successful nests during those seven years.

The annual number of nesting females also changed substantially. Using an estimated 3.03 successful nests per female per season, researchers calculated totals ranging from about 924 females in 2000 to roughly 5,827 in 2005.

The long series revealed something that a single season could never show. Estimated nesting activity increased by about 226 percent between 1999 and 2006 before appearing to level off during the later part of the monitoring period. The authors linked this strong increase in part to long-term community protection of the Itsamia beaches and surrounding waters.

Yet the annual peak remained seasonal. May could contain far more nesting attempts than December even though turtles never completely stopped using the beaches. Regional research found similar winter peaks at several northern southwest Indian Ocean rookeries and linked differences in nesting timing partly to sea-surface temperature.

Mohéli therefore carries two turtle clocks simultaneously. One is continuous, because some nesting occurs throughout the year. The second is seasonal, concentrating reproductive effort into a much stronger March-to-August pulse. Daily patrols repeated across years are what make both patterns visible.

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