Field Notes Journal Entry
A Year in the Life — Bringing the Patterns Together
What a simple monthly aggregation can reveal about behaviour, seasonality, and presence
This series began with a simple idea: to group sightings by month and see what patterns might emerge.
What has become clear, across the species considered so far, is that even this modest approach is enough to reveal a surprising richness of structure.
A Common Framework
Across birds and plants alike, the same basic method has been applied:
- Aggregate observations by month
- Plot total sightings
- Compare with a simple measure of presence
From this, a number of distinct patterns begin to emerge.
Detectability
In some species, the pattern reflects not whether the species is present, but how easily it is seen.
The Robin and Blackbird both show a late-summer dip, despite being present throughout the year. This likely reflects behavioural changes — moulting, reduced activity, or increased cover — rather than any real absence.
The species remains, but slips from view.
Phenology
In flowering plants, the pattern is more directly tied to the life cycle.
Daisy and Dandelion both show clear seasonal structures, but with important differences in timing and duration. The longer flowering period of the Dandelion produces a broader curve, while the Daisy is more tightly defined.
Here, the curve reflects the calendar of the plant itself.
Migration
For migratory species, the pattern becomes more explicit.
The Chiffchaff and Swallow show clear periods of arrival and departure, with well-defined seasonal windows. The Blackcap introduces a variation on this theme, with a predominantly migratory pattern but a small number of winter records.
Presence itself becomes seasonal.
Aggregation
In some resident species, the key driver is neither detectability nor presence, but how individuals are distributed.
The Starling shows a pronounced winter peak driven by flocking behaviour, while the Woodpigeon presents a more gradual version of the same effect — present throughout the year, but encountered in larger numbers at certain times.
The species is constant, but its visibility in numbers is not.
Presence and Abundance
One of the more useful distinctions to emerge from these comparisons is the difference between presence and abundance.
Some species vary primarily in whether they are present at all. Others are always present, but fluctuate in how many individuals are encountered.
This distinction helps to explain why two charts — sightings and presence — sometimes align closely, and sometimes diverge.
A Simple Method, A Rich Result
What is perhaps most striking is how much of this can be seen without complex modelling.
A simple monthly aggregation, applied consistently, is enough to reveal:
- Behavioural shifts
- Seasonal cycles
- Movement patterns
- Changes in social structure
Each species adds a slightly different perspective, but all fit within a common framework.
Closing Thoughts
These observations are drawn from informal records, collected over time rather than through structured survey. As such, they should be read as indicative rather than definitive.
Even so, the consistency of the patterns suggests that the underlying signals are real.
What began as a simple exercise has become a way of looking more closely at familiar species, and of recognising that even common observations can contain a great deal of information.
It will be interesting to see how this framework holds as additional species are added.